As the Obama campaign ramped up its attacks on Bain Capital, Mitt Romney’s former private-equity firm, the company on Monday took the rare step of defending its record.

The firm was responding to a new ad that focuses on Ampad, a company purchased by Bain in 1992 that laid off 250 workers at an Indiana plant before going bankrupt in 2000.

“We acquired Ampad from Mead Corp. in 1992, and grew the overall business during the four years we controlled the company,” Bain’s statement said. “Our control of Ampad ended in 1996, fully four years before it encountered financial difficulties due to overwhelming pressure from ‘big box’ retailers, declines in paper demand, and intense foreign price pressures.”

The six-minute video from the Obama campaign describes how, in 1994, the Bain-owned Ampad bought SCM, a hanging-file-folder factory in Indiana. All 250 workers at the SCM plant were quickly laid off and invited to reapply at a lower wage.

Ultimately, Bain made nearly $100 million from its investment in Ampad.

“Despite political attacks that emphasize the few companies that have struggled, the facts are that during Bain Capital’s ownership, revenues grew in 80 percent of the more than 350 companies in which we have invested,” the firm’s statement said.