Controversial Londoner O'Sullivan, 36, announced he would not be taking part in tour events for the foreseeable future, calling the new WPBSA contract "too onerous" and claiming he could not commit to its requirements.
But WPBSA chairman Jason Ferguson insisted that their new stipulations did not demand signatories play certain events, calling O'Sullivan's claims a "misconception".
"I’d like to clarify the WPBSA's position in relation to the official players' contract and end the misconception that players are being ‘forced’ into playing certain events," Ferguson said. "The contract is there to protect the players’ income derived from the tour, and the sport as a whole.
"Once players have signed the contract they are free to choose which events they wish to play in.
"It is the WPBSA's duty to ensure that all of the players are treated equally and therefore it is our belief that all players should sign the same contract.
"We do not believe it would be in the interest of the membership as a whole if one player was allowed a different contract which could give that player additional appearance money."
Ferguson did, however, leave the door open to the Rocket's return, saying he would be welcome to play whichever tournaments he felt appropriate - provided he signed the contract.
"Ronnie O’Sullivan of course is free to sign the contract at any time during the season which would make him eligible to play in World Snooker events, but it is important to note that signing the players' contract does not in itself compel any player to enter any World Snooker tournaments," Ferguson added.