Damon Corp. disclosed that it is negotiating...

Damon Corp. disclosed that it is negotiating with an unidentified group that wants to buy the Needham Heights, Mass., laboratory chain. The disclosure came less than two weeks after Damon said it was negotiating to be bought by an investment group led by American Magnetics of Sherman Oaks. American Magnetics heads Nomad Partners, which earlier launched an unsolicited $201-million bid for Damon.