More than 300 addresses that disparage BofA , including 'BrianMoynihanBlows.com' and BrianMoynihanSucks.com, referring to the bank’s chief executive, were registered on December 17.

Domain names that targeted Charles Noski, the chief financial officer, and board member Charles Rossotti were also registered.

The company doing the registering was MarkMonitor, a San Francisco-based group that protects the identity of large corporations.

MarkMonitor was not immediately available for comment and BofA declined to comment.

While it is not uncommon for companies to purchase domain names in an effort to prevent critics from using them, the registration of so many names at once is unusual, said Andrew Allemann, editor of Domain Name Wire, which tracks the buying and selling of web addresses. (Listen to New York Times Business Reporter Andrew Ross Sorkin's comments here.)

Mr. Allemann, who first wrote about the BofA names on his blog, said it was also rare for companies to purchase addresses that could be used to denigrate individuals. “Most of the time they are trying to protect the corporate brand,” he said.

BofA would have good reason to step up brand protection now.

The bank has come under scrutiny for its handling of mortgage modifications and was recently sued by the attorneys-general of Arizona and Nevada over potentially fraudulent practices.

BofA is also widely believed to be a target of WikiLeaks, the internet website whose founder Julian Assange has threatened to release a large cache of documents that, he says, will embarrass a big bank.

Mr. Allemann said domain names can be purchased for as little as $10 in annual fees, making it a relatively inexpensive way to protect corporations or individuals.

Not every domain name critical of the bank was registered. A website already exists called 'BankofAmericasucks.com' that serves as a forum for customers to air their complaints.