21-year-old Mexican Gutierrez is replacing Sauber's McLaren-bound Sergio Perez, presumably to keep the Swiss team's main backer Telmex happy.
Telmex is the Mexican company headed by billionaire Carlos Slim, whose son and namesake is directly involved in the handling of Perez's career.
But it's a slightly different situation for Gutierrez.
Asked if Slim told him he would be stepping up from the reserve role after three years to finally race for Sauber in 2013, Gutierrez said: "No. I have had a contract for four years with Sauber.
"My deal is with them," he insisted to Spain's El Confidential.
"Obviously, the relationship with Carlos is very close because they are my sponsors, but unlike Checo (Perez) they have not been my managers.
"We have always worked with them as a sponsor, and they have been very supportive, but I have my relationship with Sauber and a programme that has been developed over time with them," added Gutierrez.