Abstract: Methods, systems, and apparatus, including computer program products, for generating or using augmentation queries. In one aspect, subject phrases for detection in content are identified. Each phrase has a corresponding cardinality of terms. First hash sets for each of the subject phrases are generated, each first hash set including first hashes of bigram term subsets for each of the phrases. Sub-phrase scores for each of the hashes based on the cardinality of each phrase are assigned. The sub-phrase scores a used to detect the subject phrases in hashes of portions of received content. Other implementations of this aspect include corresponding systems, apparatus, and computer program products.

Abstract: Methods, systems, and apparatus, including computer program products, for generating or using augmentation queries. In one aspect, a set of phrase terms of a phrase are received in first ordinal positions, and a set of first hashes for each of the phrase terms. Concatenated hashes from the set of first hashes are generated. Hashes of content terms for received content are compared to the concatenated hashes to determine if a phrase is detected in the content.

Abstract: Methods, systems, and apparatus, including computer program products, for selective presence notification are provided. In one general aspect, a plurality of presence notification messages are monitored. Each presence notification message may include address information identifying at least one of a recipient or a sender of the presence notification message. Based on the address information a determination is made as to whether a presence notification message is allowable. If it is determined that the presence notification message is allowable, the transmission of the presence notification message is allowed.