The e-mails include what appears to be an exchange on Nov. 9, 2010, between Aaron Barr, HBGary Federal’s chief executive, and John W. Woods, a Hunton & Williams partner who focuses on corporate investigations. Mr. Barr recounted biographical tidbits about the family of a one-time employee of a union-backed group that had challenged the chamber’s opposition to Obama administration initiatives like health care legislation.

“They go to a Jewish church in DC,” Mr. Barr apparently wrote. “They have 2 kids, son and daughter.”

A week later, Mr. Barr submitted a detailed plan to Hunton & Williams for an extensive investigation into U.S. Chamber Watch and other critics of the chamber, including the possible creation of “in-depth target dossiers” and the identification of vulnerabilities in their computer networks that might be exploited.

Another PowerPoint presentation prepared for Hunton & Williams said the research that HBGary Federal and its partners could do for the law firm on behalf of the Chamber of Commerce would “mitigate effect of adversarial groups” like U.S. Chamber Watch. The presentation discussed the alleged criminal record of one leader of an antichamber group, and said the goal of its research would be to “discredit, confuse, shame, combat, infiltrate, fracture” the antichamber organizations.

HBGary acknowledged Tuesday in a statement that it had been the victim of a “criminal cyberattack,” but suggested that documents placed in the public domain might be “falsified.”

The other two businesses referred to in the apparent proposals as planned partners in the corporate investigations put out statements that distanced themselves from HBGary Federal but did not say the documents were fake.

The co-founders of Berico, Guy Filippelli and Nick Hallam, confirmed that Berico had been “asked to develop a proposal to support a law firm” that was helping companies “analyze internal information security and public relations challenges,” but said their proposal had been limited to “analyzing publicly available information.” They called efforts to target people “reprehensible” and said they were breaking all ties to HBGary Federal, a move that Palantir executives also said they were making.