Good observation, I believe Berkshire already owns some IR.... Mr. Buffett mentioned IR maybe 6 months ago in an interview..... he said he couldn't ignore the bargains in Europe and had purchased shares in 4 companies.
would fall within his hint of an offer they made but couldn't close. Peltz has had a history of being in stocks that have connections to Buffett in the past. IR has Trane and other "housing" type beneficiaries of a turn in housing. Could be the one he made overtures to.