The Belgium midfielder, along with team-mate Leighton Baines, has been linked with a move away from Goodison Park this summer, with both players reported targets of Manchester United manager David Moyes, who knows both well from his time with the Toffees.
The transfer window does not close until 11pm on Monday, September 2 but Martinez, at his first briefing of the new season, said: "Marouane had a buy-out clause where it was very straightforward. If someone met that valuation, the club had no say.
"That finished on July 31 so you can imagine during that period everyone was a bit expectant about what would happen. Once that date went, you just focus on working for the next season.
"I'm not concerned at all at the moment (about players leaving). The window is open and until it closes you're going to get speculation, you're going to get a lot of talk, not just at Everton. It's the norm."
Martinez is still in the market for new signings himself, having brought Gerard Deulofeu and former Wigan trio Joel Robles, Antolin Alcaraz and Arouna Kone to the club this summer.
But he revealed the form of teenagers Ross Barkley and John Stones has made him even more confident about the squad he already has.
"I've been very impressed with the youngsters," the former Wigan boss said. "Ross Barkley and John Stones have really surprised me. I knew they had a fantastic future, but what they've got is a very special present, and that excites me.
"You always need to keep looking to try to help the players we've got at the club but we're not looking for a specific number. If we don't bring anyone in, I'll be happy."
Martinez was excited by the performances of Baines and Phil Jagielka in England's victory over Scotland on Wednesday night.
Source: PA
Source: PA