The Baggies No.9 is one of four Albion players with such a clause in place, which allows other clubs to swoop in and take them should they meet the figure this summer.
Record signing Nacer Chadli also has a relegation release clause, which is understood to be in the same region as Rondon’s.
Jonny Evans has a £3m relegation release clause in his contract, and another unnamed player also has one in place.
Over the weekend there were reports that Rondon would be able to leave for £8m this summer, but the Express & Star can reveal his release fee is actually more than double that.
The Venezuelan has been one of Albion’s better performers in recent weeks.
He has a reputation for being a goal-shy striker but has netted five times in his last 13 games, and is one of the few players who came out of Alan Pardew’s reign with his head held high.
Albion turned down a £32m bid for Rondon from Chinese side Tianjin Quanjin on the final day of the January 2017 transfer window, but it’s understood the striker was not keen on the move.
Selling him then would have also left the Baggies dangerously light up front with just Hal Robson-Kanu as the only recognised senior striker left in the squad.
The Baggies also turned down a deadline day bid for Chadli from Swansea last summer because former chairman John Williams wanted £25.5m for the Belgian.
Chadli’s season has been wracked with injury since then, and he has only played 16 minutes for the Baggies since October.
Skipper Evans is likely to leave on the cheap this summer, because of the tiny release clause put in place when he joined in 2015.
And it could be a busy summer in the transfer market for the Baggies, with Jay Rodriguez, Craig Dawson, James McClean and Jake Livermore all likely to attract interest.
However, shot-stopper Ben Foster has already pledged his future to the club, regardless of Albion’s inevitable relegation, and has urged some of his team-mates to do the same.
Claudio Yacob has not triggered an option to extend his contract, as reported elsewhere, but the club are planning to sit down and discuss a potential new deal with the Argentinian midfielder once the season finishes.