A Sears spokeswoman said the company had not set a date by which to sell the stake.
Prodigy, co-owned by Sears and IBM Corp., had been rumored up for adoption by both parents for most of 1995. The service has 1.5 million subscribers, compared with 5 million for America Online and 4 million for CompuServe.
Prodigy insiders say IBM still has not decided what it wants to do with its stake in the online service, even though it had been known for months that Sears was considering bailing out.
Sears' move comes a day after H&R Block said it was spinning off CompuServe, its online service company. Analysts say CompuServe is in a much better position financially than Prodigy is.