Athletic Bilbao boss Ernesto Valverde has admitted that "there might be some departures" this month.
Bilbao finished fourth in La Liga last season but have struggled this term, with 19 points from 17 games leaving them 12th.
"There might be some departures," Valverde told reporters.
"Every so often I speak with the players and I have to do that, especially when they're not being included in the squads. In pre-season I spoke with Gaizka Toquero, Jon Aurtenetxe and Kike Sola, explaining that it might be better for them to go out on loan.
"In the case of Aurtenetxe, I said I'd prefer him to stay. Now we'll have to see. It all depends on what offers there are, if they're of interest to the players and to the club."
Bilbao are restricted to signing Basque-only players.