Mark Papermaster, a 26-year veteran of IBM, filed a countersuit Thursday, less than a week after Judge Kenneth Karas Karas' temporary injunction on Nov. 7 was in response to a lawsuit IBM filed in late October, when the computer company charged Papermaster with violating a 2006 non-competition deal by accepting a position at Apple to head its and development.

In the countersuit, Papermaster again argued that Apple and IBM are not really rivals. "Apple and IBM are not significant competitors," he said in the filing. "IBM primarily provides business services, while Apple's primary business is the design, manufacturing and marketing of consumer electronic products."

Papermaster also asserted that the non-competition agreement he signed while at IBM was "unreasonably broad" because it tried to restrict him from working for "any company that engages in competition with his former business unit to any extent, even if Mr. Papermaster will not be working for the part of the company that does."

IBM has charged that Papermaster, who during his career with IBM was involved in the development of the Power line of microprocessors and in charge of the company's blade server development, might be working on similar ventures at Apple. Last April, a chip design firm that creates high-end, low-power processors, a fact IBM mentioned in its Oct. 22 lawsuit. Papermaster has denied that his duties at Apple will include anything related to P.A. Semi, or to personal computer design.

Ultimately, the non-competition agreement is unenforceable, Papermaster's lawyers argued, because of where he lives and where Apple is located. The agreement, they noted, is governed by the laws of the state of New York, where IBM is headquartered., while Papermaster lives in Texas and Apple is based in California. "Both states hold that such non-competition agreements are unenforceable as a matter of public policy," the countersuit said.