Abstract: Methods and systems of securely exchanging customer data are provided. The exchange may be done in privacy-preserving and/or privacy-protective fashion. Customer data from multiple merchants, including transaction data for a first product between a first customer and a first merchant, is maintained in a customer data pool by an e-commerce platform. When a second merchant associated with a second product requests new customer data, a product (i.e., the first product) relevant to the second product is identified. A collection of customers who indicated interest in the first product (including the first customer) are identified from the customer data pool, and a target audience is generated proportional to customer data exchanged by the second merchant with the customer data pool. Communications from the second merchant are then provided to the target audience without disclosing their customer data to the second merchant.