The shares would be worth more than $400 million, based on EMC's current stock price. The stock was recently trading at $40.42, down 28 cents.
The shares represent about 32 percent of the couple's holdings in EMC, a spokeswoman for the company said.
Co-founder Richard Egan currently serves as chairman emeritus, and he has been has been a member of the board of directors since 1979. Maureen Egan, his wife, joined the board in March 1993 and resigned in the first quarter of this year.
Richard Egan was nominated in March by President George W. Bush to serve as ambassador to Ireland.
The registration is part of a "continuing practice" of portfolio diversification by the Egans, said the spokeswoman, who noted that the couple registered earlier in the year to sell an additional 2 million shares, but has not yet sold them.