Turns out CompuServe was purchased by H&R Block, looking ahead to online tax transactions, back in 1980. And Prodigy, launched four years later in 1984, was a co-venture between Sears, IBM and CBS. (CBS dropped out in 1986 as the company divested non-broadcast assets.)
In 1990, CompuServe led with 600,000 subscribers; Prodigy was at 400,000. (More details for both on Wikipedia.)
But soon AOL triumphed over both until ... ?
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