A policy followed by the NLRB pursuant to Midwest Piping & Supply Co., 63 N.L.R.B. 1060 (1945) marked by complete neutrality by employers in rival union situations. This doctrine was followed for the 37 years from 1945 until 1982. As a result of the case RCA Del Caribe, Inc., 262 N.L.R.B. 963 (1982), an employer has to deal with an incumbant union even if a rival union has filed a valid election petition. In the case where there is no incumbant, the Board has required the employer to take a position of complete neutrality only after the filing of a valid election petition. Before such a filing, the employer is free to recognize a union if that union represents "an uncoerced, unassisted majority" of employees. Bruckner Nursing Home, 262 N.L.R.B. 955 (1982).