Online betting systems

Abstract

Online betting systems are disclosed in which a number of players may offer and accept bets online on the outcome of events, for example sporting events. Each player may be both offering bets and accepting them. By linking together, in a central server operating the system, databases reflecting betting data relating to bets which have been both offered and accepted, but which are outstanding because the outcome of the event is not yet known, and reflecting account data of the players, a players theoretical exposure at any one time may be calculated, and action taken to update the betting database data if the theoretical exposure would exceed the amount held in the account of the player concerned. By carrying out that calculation ignoring unmatched offers which each player has made, unnecessary restrictions do not need to be placed on the offers made by each player. Once an offer is accepted, however, a fresh calculation is made and this can result in previously existing other offers being deleted. This approach improves the liquidity of the system and enables players to operate to a greater extent, thereby improving the return to the operator of the system.

Description

This invention relates to online betting systems and, in particular, to online betting systems of the exchange type which seek to match bets offered by users of the system, hereinafter called “players”, on a real time basis.

Recent years have seen a substantial rise of betting activity carried out via the Internet. In standard fashion, the first Internet applications were effectively a replication using the Internet of existing betting arrangements, for example where a bookmaker offers odds on particular outcomes, for example who will win a horse race or football match. The offer may change in time, but those who accept the offer place bets with the bookmaker and, if the outcome desired by the player then occurs, the bookmaker pays out. In such a scenario, the bookmaker acts as a common contractor with a large number of individual players, each betting transaction being between bookmaker and player, though the odds offered by the bookmaker may vary in time depending on bets already placed, but where the outcome is still unknown.

The Internet is perfectly suited to act as the communications medium between players who hold an account with the bookmaker and the bookmaker itself, with bets placed being debited from the player's account and winnings credited to it.

With the advent of the Internet, however, the possibility arose of individual bets being made between individual players, rather than between player and bookmaker. Because of the abilities of computer-based systems to accept, classify, search and present data, it is possible to run betting systems online where individuals can post offers, others can accept them, individual contracts can be made and the stakes are shifted to the players' accounts. The operator of the system can derive income from charging players in any appropriate fashion, and, of course, the ability to store and manipulate very substantial amounts of data also extends to the straightforward ability of storing an accurate and auditable log of players' activities, thus enabling the detail of any betting transaction to be examined in depth and at will.

In the description which follows of an Internet-based online betting system, both as regards known betting systems and with respect to the improved betting system in accordance with the invention, certain terms are used which it is useful, for clarity of explanation, to define. In this specification, accordingly, the following terms have the following meanings:

Player

• • A user of the system, whether exclusively offering bets for other players to accept, or accepting offers made by other players, or engaging in both activities.

Event

• • Something which has an outcome which is unknown when a bet is offered and accepted, but where the outcome becomes apparent subsequently, when the event occurs.

Selection

• • A condition that may or may not hold relating to the possible outcome of an event.

Market

• • A collection of selections relating to a particular event. If the collection includes all possible outcomes of the event, and in such a way that exactly one of those outcomes will obtain once the event has occurred, the market is said to be a “complete” market.

Back Bet

• • A bet that a certain selection will obtain following the occurrence of event.

Lay Bet

• • A bet that a certain selection will not obtain subsequent to the occurrence of the event.

Win

• • The amount of money won on a back bet or lay bet following the occurrence of the event so that the outcome in respect of which the bet was placed becomes known.

Selection Win

• • The sum of the back win plus all lay wins of other selections in the market.

Complementary Selection Win

• • This operates if the market is not complete, or if a player has not made bets on all selections, the complementary selection win is the sum of all lay wins of the other selections.

Exposure

• • The maximum amount of money which a player may lose if all bets accepted by him, or offered by him and accepted by others, resolve against him.

Bet Exposure

• • The exposure that results from all bets that are currently agreed, i.e. the stakes minus the least of all selection wins including the complementary ones.

Theoretical Exposure

• • The worst possible scenario, taking into account outstanding offers. In other words, the theoretical exposure is the stakes of accepted bets and the stakes offered for backing selections deducting the least combination of a selection win and the lay stake minus the back stake offered on that selection.

It should be noted that neither the bet exposure nor the theoretical exposure can ever be less than zero, because events may be cancelled.

In a known Internet betting system, the organiser of the system provides a central computer which is conveniently identified as a “betting server”. This can be accessed via Internet connection by individual users of the system, using any remote computing device which is compatible with the Internet, for example a mobile telephone, hand-held computer or PDA, a portable or laptop, or a personal computer, or, indeed, a terminal on a computer system.

What is important is that the computer apparatus in question is under the control of the particular user and, of course, that the user is identified to the system. This may be achieved by a customary registration process usually involving an application which may be completed online, and acceptance of that application by the betting server (i.e. by the parties owning and controlling the use of the betting server). By means of appropriate funds transfer, the player may deposit an appropriate sum of money with the owners of the system, and this sum can be fed in as part of the data held by the betting server on that player's account. Although the detailed implementation may vary, the betting server may be operated to update and maintain an “account database” which keeps track of the players and their deposits, and which adjusts the amounts in the individual players' accounts once the outcome of an event is known.

In an exchange betting system operated in this way, the identities of the individual players are accordingly known to the system, but they are not known to the other players.

Players who wish to participate in an exchange betting system of this type may make offers relating to certain outcomes of certain events at given odds. Those offers can be made using any appropriate interface depending upon the computer used by the player. As soon as an offer is received by the betting server, the data which the offer constitutes is fed into a central “bet database” and each offer can then be viewed by other players. The central bet database enables bets to be categorised and sorted so that players who are looking for a bet to accept may view bets in a given area (where they reckon they have the necessary knowledge or experience to bet and win) without difficulty. Typical categories would be football, horse racing or stock movements. Sorting may also occur e.g. by size or stake. If a player, on viewing a range of available offers, decides to accept one of the offers, then they can communicate with the system in simple and straightforward fashion using, for example, a keyboard and/or mouse, or a combination of the two, to indicate that they accept the offer. The bet database is then updated appropriately.

Once a bet offered has been accepted, there is essentially a betting contract between the two players which will be administered by the betting server. The outcome of whatever the event is relating to an accepted offer will, once known, determine which player wins, and the relevant amount of money can then be removed from the account of the losing player and placed in the account of the winning player.

The system may automatically advise both players, and make the appropriate adjustments to the respective players' accounts once the outcome of the event is known. Most bets are of the simple sort where one of the players wins the money betted by the other.

In order to carry out these transactions and notifications, the betting server may be thought of conceptually as embodying three main functional building blocks, viz. a communications building block acting as an interface between the players and the other functional parts of the server, a betting processor component which continuously feeds data into, deletes data from and generally updates a bet database, and, as a third component, an accounting processor system, including an account database storing financial transaction details for each player, the identity of each player, and the amount of money standing to the credit of his/her account.

The classical known way of operating an online exchange betting system of this type is to provide that when any player places offers on the bet database, funds are reserved in the account database so that if the offers are all accepted, the exposure of the player concerned is not greater than the sum of money deposited in the account database by them.

Operating in this way is disadvantageous because circumstances can arise in real time where the exposure of an individual player, as reflected in the account database, approaches the amount of credit allocated to that player in that database. At that point, the system needs immediately to stop any further offers being made.

Although the system has been specifically described above with reference to a disjunctive market, i.e. one where the selections do not overlap, it is clear that it may be applied analogously to other types of market by use of appropriate software to run an online betting system in such a market, for example a handicap market, e.g. in which there are overlapping selections. An example is in football where one selection is for A to win by 3 goals and another for A to win by 4 goals. If the latter selection holds, so will the former.

By working out exposures from data in the bet database and combining those exposures with data in the account database, unnecessary curbs on actions by players are eliminated without prejudicing the position of the operator of the system.

In accordance with the present invention, there is provided an online betting system enabling bets to be made bilaterally within a group of players, comprising a central server, a plurality of remote computer-based devices programmed to interact with the central server to enable communication between each device and the central server via the Internet programme means in the central server for storing and processing betting data stored in a bet database and each remote computer-based device having a display means enabling a player to view information in the bet database held by the central server and having input means enabling the player to input information, via the remote device, into the central server, means in the central server to receive and store information relating to offers posted by players, means in the central server for storing and processing data corresponding to the amount of money in an account held by each player with the operators of the central server, means for calculating from betting data in the bet database server, on receipt of an offer or on acceptance by another player of a betting offer posted by way of input to the central server by a player, the exposure of each player, means for computing a theoretical exposure from the bet exposure, the outstanding offers and the aggregate winnings means enabling the operator of the system to define an acceptable level of theoretical exposure, means for calculating if the acceptance of other offers placed by the player will cause the theoretical exposure to exceed the acceptable level and, if such occurs, to remove from the bet database sufficient offers made by the player to reduce the theoretical exposure to below the acceptable level.

In practice, this is done by programming the betting server to total for each player, continuously and in real time, the total of bets matched between that user and all other users of the system, including details of the event and the selection, and to total the bets matched in terms of possible winnings and stakes betted, both lay bets and back bets, whereby to compute the theoretical exposure for each player. Unmatched bets are only taken into account when computing the theoretical exposure.

Preferably, the central server includes means for receiving and storing budget limits input by a player, means in the server to receive and store prioritisation and budgeting information relating to the offers, and the means for removing offers operates in accordance with the prioritisation and budgeting information

There is accordingly a fundamental operational difference between an exchange betting system of known type and a system according to the present invention.

Current exchange betting systems operate on the basis that offers made and not accepted are treated the same as offers made and accepted. Specifically, all offers made by a particular player (whether matched or unmatched) result in the player's available funds being ‘reserved’ against these offers on a ‘dollar-for-dollar’ basis, i.e. one dollar (or other currency as applicable) offered, whether matched or unmatched, results in the deduction of one dollar from the offering player's available funds in their account, resulting in such funds not then being available for the making of other offers or accepting other players' offers. This practice effectively limits the use to which players' funds may be put as it ties up funds in offers which may or may not be accepted, reducing the amount available for making other offers or accepting offers made by other players.

Using a system in accordance with the invention, a series of offers may be made in excess of a player's available funds. This is done by treating unmatched offers differently to matched offers. More specifically:

• • a) the placement of offers does not lead to funds being ‘reserved’ on a ‘dollar-for dollar’ basis; instead, funds remain available for the making of other offers until such time as one or more of the offers made are matched;
  • b) only when an offer is matched are a player's funds relating to the offer ‘reserved’, at which time the availability of funds for other unmatched offers is automatically re-assessed and reduced accordingly;
  • i) where insufficient funds remain to cover unmatched offers made, these offers are automatically suspended from the market and may not be then accepted by other players;
  • ii) where sufficient funds remain available to cover unmatched offers made, these offers remain on the market for acceptance by other players.

To ensure player accounts never become overdrawn, the system according to the invention provides real-time tracking of a player's available funds in relation to offers accepted by other players. At the technical level, this may be achieved by enabling the betting server to correlate data in the bet database with data held in the account database in real time transactions so that the acceptance of offers, i.e. the occurrence of a matched bet, leads to changes in the data held in the account database regarding the player concerned.

The system according to the invention thus maximises a player's use of his/her available funds by allowing the player to exceed their available funds for the making of offers, while ensuring that the player's actual exposure (the total possible loss from the player's offered bets accepted by other players) is never greater than their funds available and while ensuring that the market is not flooded with offers that cannot be accepted. This is achieved by computing the bet exposure on all accepted bets and adjusting the funds available accordingly, and by the use of the theoretical exposure calculation, which compares a multiple, for example 100, of the amount held in the player's account with the theoretical exposure, i.e. the liability of the player on the assumption of the worst possible outcomes for that player of all events, taking into account winnings, matched bets and unmatched offers and possible outcomes. This enables a player to make offers which, if they were all accepted by other players and the bets then lost, would expose the player to a liability of 100 times the amount in their account.

The way in which the betting server forming part of the system of the present invention may operate will depend on the programming, and the detailed programming may be produced by those skilled in the art to suit the particular requirements of any promoter or system operator of the betting system of the present invention. The way in which the promoter earns money from the system can be any permissible combination of subscription, commission, or other charging mechanism. The way in which systems according to the present invention enhance use of players' funds by not cutting off potential transactions due to ostensible lack of fundability, means that the player's money is put to best use and maximum use, in turn benefiting both player and system operator.

The betting system of the invention is thus characterised by programme means having a core functionality enabling the system to compute the bet exposure and the theoretical exposure on a market for a given player, and to remove offers made by that player from the bet database if the theoretical exposure exceeds their account balance by more than is stipulated by the exchange operator.

The theoretical and bet exposure of a player on a market with disjunctive selections, i.e. a market where at most one of the selections will turn out to be the case, may be calculated from the following equations:
theoretical(m,u)=Sum[s in m] (stake(s,u)+backOffer(s,u))−Sum[s in m](layWin(s,u))−Min[s in m](rawWin(s,u)+backOffer(s,u)−layOffer(s,u))
exp(m,u) Sum[s in m](stake(s,u))−Sum[s in m](layWin(s,u)−Min[s in m] (rawWin(s,u)).
In these equations:

• theoretical(m,u) is the amount a player u can lose on a market m, if the worst combination of accepted offers and actual outcome should occur. It is never less than zero because all events can be cancelled;
• exp(m,u) is the amount that a player u can lose on a market m from his currently accepted bets, i.e. the bet exposure of u on m. It is never less than zero because all events can be cancelled;
• s in m is the set of all selections s in a market m;
• stake(s,u) is the amount betted on a selection s (back and lay) by a player u;
• layWin(s,u) is the amount that a player u will win if a selection s does NOT hold;
• backOffer(s,u) is the amount offered as stake on bets that a condition will hold;
• layOffer(s,u) is the amount offered as stake on bets that a condition will NOT hold;
• backWin(s,u) is the amount that a player u will win if a selection does hold; and
• rawWin(s,u) is backWin(s,u)−layWin(s,u), i.e. the impact on winning that is specific for player u on selection s.

From the formula, it can be seen that, when backing a selection apart from the stake, the exposure is affected only if the bet is on the selection with the least rawWin. Thus, the marginal rebate rebateBack(b,w,s,u) on exposure for player u of betting the amount b to win w on backing selection s is given by the equation:
rebateBack(b,w,s,u)=
zero if s !=minsel(u,market(s))
rawWin (minsel2(u,market(s))), if less than w & s=minsel(u,market(s))
w otherwise
where:

• market(s) is the market where s is a selection
• minsel(u,m) is the selection with the least raw Win(s,u) for player u of all selections s in market m, and
• minsel2(u,m) is the selection with the second least raw Win(s,u) for player u of all selections s in market m.

For lay bets, the change of bet exposure apart from the stake is rebateLay(b,w,s,u) for player u betting stake b against selection s to win w and can be computed as:

rawWin(s)−rawWin(minsel(u,market(s)) if less than w

w otherwise if s !=

minsel(u,market(s))

zero otherwise.

In betting systems according to the invention, the above equations are calculated and continuously updated. This may be effected using standard programming, but, in order to do so, the betting server has to be programmed to acquire data both from the bet database and from the account database which contains details of the player, and the amount of money in the account database standing to that player's credit. This can be continually repeated with fresh calculations being done each time the player decides to take up a betting offer from another player and each time one of the offers made by that player is actually taken up by another player.

In a further development of the online betting system according to the invention, the system may be arranged to enable a player to allocate funds in his/her account to specific betting areas. Instead of calculating the player's theoretical exposure taking into account the player's entire account balance, it is possible to apportion/segregate the balance across different events or bet types and apply a multiple to each of these separately. For example, a £10k account balance could be allocated as follows:

EPL £5k (×100=£500,000 in offers on EPL)

NFL £4k (×100=£400,000 in offers on NFL)

NHL £1k (×100=£100,000 in offers on NHL)

rather than just enabling the player to post up to 1 million in offers regardless of sport or bet type. This, for example, prevents all of the player's NFL offers being cancelled because of £90k of matched EPL bets. The multiple could be varied by sport or by bet type.

The system may also be programmed to enable players to decide how their offers are cancelled. For example:

• • First in/first out—the player's first offer is cancelled first (last offer cancelled last)
  • First in/last out—the player's first offer is cancelled last (last offer is cancelled first)
  • Pruning—all offers are reduced versus cancelling
  • Priority—to give prioritised treatment to certain offers to ensure they are cancelled last
  • By depth of market priority—give priority to offers that are priced further from mid rate.

The invention is further explained and illustrated with reference to the accompanying drawings in which:

FIG. 1 shows diagrammatically an Internet betting system in accordance with the invention;

FIG. 2 shows the detail of the betting server shown in FIG. 1;

FIG. 3 sets out in block diagram form the data fields which have to be completed for a player in order to participate in the betting system according to the invention;

FIG. 4 is a flow diagram of how the system according to the invention adjusts any bets that a player may offer in accordance with his financial exposure at the time; and

FIG. 5 is a diagrammatic view of a specific scenario showing a possible train of events.

Turning first to FIG. 1, this shows the betting system in diagrammatic form consisting of a betting server 1 which may be connected via the Internet conventionally represented as a cloud to any one of the individual computer communications devices 2 to 8 possessed by and operated by individual users. The individuals, each identified by a stylised figure labelled “player”, may communicate with the betting server 1 via the Internet 9 using their respective communications device, for example a laptop computer 3 or a mobile telephone 8.

The broad internal arrangement of the betting server is shown in FIG. 2. As can be seen, it is connected to the Internet 9 and the programme is such that the server provides a website which is used by the players as will appear in more detail below. Because it is a website-based system that is illustrated, the betting server contains a plurality of web processors 12 which deal with the interaction between the server and each player via a conventional graphic user interface, and which are in turn connected to a number of further processing units inside the server. These consist of a set of betting processors 14 which constantly update a bet database 15 and, separately, a set of accounting processors 16 which constantly update an account database 17.

In accordance with the invention, the belting processors are arranged to be able to retrieve information from the accounting processors so as to ensure that the maximum exposure is always less than the amount standing to the player's credit, despite changes in the data held on the accounting or bet databases.

As noted above, in order to use the system, a player needs to provide data to the betting computer and this is done by inputting appropriate data and storing that data internally of the server. For any given player, it is convenient to calculate and hold the relevant data for each particular player and for each particular selection. This can be used, as shown in FIG. 3, to construct a “summary” which contains the total of bets matched in terms of possible winnings and stakes bet, both on the lay side and on the back side. The least favourable or least win selection is an important term when computing the bet exposure of the player, or specifically the bet exposure following the placing of an offer or acceptance of a bet, as set out above.

As can be seen from FIG. 3, for each given player, i.e. for each unique user ID, certain data is derived and stored until overwritten by subsequent data.

The exact way in which the player's activity changes his status internally of the betting server is easiest seen by considering a simple, but realistic, example. The example chosen for consideration is the two events being the semi-finals of a league championship. By this time, there are four teams remaining, which can be denoted A, B, C and D, with A playing B and C playing D.

If we now consider the first player, let us assume that he has a credit of £1000 and he wishes to make the following offers:

1. £500 at odds of 1.95 to 1 for A to beat B.

2. £500 at odds of 1.95 to 1 for B to beat A.

3. £500 at odds of 1.95 to 1 for C to beat D.

4. £500 at odds of 1.95 to 1 for D to beat C.

If we now assume that another player decides to accept offer number 1, but only to the extent of £400, then the original player can now offer the following:

1. £100 at odds of 1.95 to 1 for A to beat B.

2. £500 at odds of 1.95 to 1 for B to beat A with offers 3 and 4 as before.

If a third player now accepts the fourth offer in its entirety, the total amount wagered is now £500, £400 from the second player and £500 from the third, so the first player has now effectively reserved £900 out of his original £1000. However, he may still offer £100 at odds of 1.95 to 1 for A to beat B and the original second and third offers. The second offer can still be made because it is opposed to matched offer number 1 while the third can be made because it is opposed to matched offer number 4.

It is necessary sometimes, however, to adjust outstanding offers according to the available funds. Again, this is done by essentially integrating the accounting system, the matching process and the register of offers. When an offer is made, the programming of the betting server causes a check to be carried out to ensure that the corresponding funds are available to enable the player in question to enter the specific wager proposed. Funds do not need to be reserved, but the maximum possible loss is recorded at the same time as any offer is made and when the offer is wholly or partly matched by another player, the funds are then reserved by the betting server as necessary to enter the matched wager. The remainder of the offer (if not taken up entirely) and the maximum remaining loss can be computed and recorded with the offer. If, as a result of the match, or because of other financial transactions made to the player's funds in the accounting system, the available funds have decreased, the set of outstanding offers may be pruned by calculating the theoretical exposure of the player making the offers including any exposure rebate that occurs because of opposing offers.

This is shown diagrammatically in FIG. 4.

In practice, operation of the system in real time by a plurality of users can be seen as involving three conceptual stages, the first being the betting process, the second a matching process and the third, which is the part of the process resulting from the system in accordance with the invention, being one which, following checking of the accounts, removes offers being made by a player from the system which that player cannot fulfill in a worse case scenario.

This is shown diagrammatically in FIG. 5.

Thus, by constructing a betting system using a betting server constructed to operate in accordance with the above mechanism, the players may make the maximum use of their available funds, confident that they will not find themselves in an overdrawn position, while the providers of the service will see an increased amount of outstanding and accepted offers and thus, to the extent that their return for operating the system depends on the amount of use that is made of the system, increase their return. Put simply, the invention serves to increase the liquidity of the system.

By calculating exposures from data in the bet database and combining those exposures with data in the account database, unnecessary curbs on actions by players are reduced or eliminated without prejudicing the position of the operator of the system.

Claims

1. Computer apparatus adapted to enable online betting activity to be undertaken, and enabling bets to be made bilaterally within a group of players, the apparatus comprising a central server, a plurality of remote computer-based devices programmed to interact with the central server to enable communication between each device and the central server via the Internet, program means in the central server for storing and processing betting data stored in a bet database and each remote computer-based device having a display means enabling a player to view information in the bet database held by the central server and having input means enabling the player to input information, via the remote device, into the central server, means in the central server to receive and store information relating to offers posted by players, means in the central server for storing and processing data corresponding to the amount of money in an account held by each player with the operators of the central server, means for calculating from betting data in the bet database server, on receipt of an offer or on acceptance by another player of a betting offer posted by way of input to the central server by a player, the exposure of each player, means for computing a theoretical exposure from the bet exposure, the outstanding offers and the aggregate winnings, means enabling the operator of the system to define an acceptable level of theoretical exposure, and means for calculating if the acceptance of other offers placed by the player will cause the theoretical exposure to exceed the acceptable level and, if such occurs, to remove from the bet database sufficient offers made by the player to reduce the theoretical exposure to below the acceptable level.

2. Computer apparatus according to claim 1 wherein the central server includes means for receiving and storing budget limits input by a player, means in the server to receive and store prioritization and budgeting information relating to the offers, and wherein the means for removing offers operates in accordance with the prioritization and budgeting information.

3. Computer apparatus according to claim 1 wherein the central server is programmed to total for each player, continuously and in real time, the total of bets matched between that user and all other users of the system, including details of the event and the selection, and to total the offers and matched bets in terms of possible winnings and stakes betted, both lay bets and back bets, whereby to compute the theoretical exposure for each player.

4. Computer apparatus according to claim 2 wherein the central server is programmed to total for each player, continuously and in real time, the total of bets matched between that user and all other users of the system, including details of the event and the selection, and to total the offers and matched bets in terms of possible winnings and stakes betted, both lay bets and back bets, whereby to compute the theoretical exposure for each player.

5. Computer apparatus according to claim 1 wherein the central server includes an account database system and a bet database system, and the server is programmed to enable a functional connection to be effected between the two.

6. Computer apparatus according to claim 2 wherein the central server includes an account database system and a bet database system, and the server is programmed to enable a functional connection to be effected between the two.

7. Computer apparatus according to claim 3 wherein the central server includes an account database system and a bet database system, and the server is programmed to enable a functional connection to be effected between the two.

8. Computer apparatus according to claim 4 wherein the central server includes an account database system and a bet database system, and the server is programmed to enable a functional connection to be effected between the two.

9. Computer apparatus according to claim 1 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

10. Computer apparatus according to claim 2 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

11. Computer apparatus according to claim 3 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

12. Computer apparatus according to claim 4 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

13. Computer apparatus according to claim 5 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

14. Computer apparatus according to claim 6 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

15. Computer apparatus according to claim 7 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

16. Computer apparatus according to claim 8 wherein the central server is programmed, on the outcome of an event becoming known, to advise each player with an interest in the outcome of that event of the outcome, to adjust the player's account accordingly, and to recalculate the player's theoretical exposure.

17. Computer apparatus adapted to enable online betting activity to be undertaken, and enabling bets to be made bilaterally within a group of players, the apparatus comprising a central server, a plurality of remote computer-based devices programmed to interact with the central server to enable communication between each device and the central server via the Internet, a program component in the central server for storing and processing betting data stored in a bet database and each remote computer-based device having a display component enabling a player to view information in the bet database held by the central server and having an input component enabling the player to input information, via the remote device, into the central server, a component in the central server to receive and store information relating to offers posted by players, a component in the central server for storing and processing data corresponding to the amount of money in an account held by each player with the operators of the central server, a component for calculating from betting data in the bet database server, on receipt of an offer or on acceptance by another player of a betting offer posted by way of input to the central server by a player, the exposure of each player, a component for computing a theoretical exposure from the bet exposure, the outstanding offers and the aggregate winnings, a component enabling the operator of the system to define an acceptable level of theoretical exposure, and a component for calculating if the acceptance of other offers placed by the player will cause the theoretical exposure to exceed the acceptable level and, if such occurs, to remove from the database sufficient offers made by the player to reduce the theoretical exposure to below the acceptable level.

18. Computer apparatus according to claim 17 wherein the central server includes a component for receiving and storing budget limits input by a player, a component in the server to receive and store prioritization and budgeting information relating to the offers, and wherein the component for removing offers operates in accordance with the prioritization and budgeting information.