A new Williams sponsor says the deal with the British team is not connected with the arrival of Russian driver Sergey Sirotkin.
Earlier, Russian software company Acronis backed Daniil Kvyat at Toro Rosso, but that money is now moving over to Williams.
But Acronis boss Serguei Beloussov insisted: "We started negotiating with Williams much earlier.
"Sergey was part of Renault and he could have stayed there or gone to Toro Rosso," he told the Russian source Championat.
"Our agreements do not depend on Sergey’s contract. Of course, the fact that he is at Williams is a plus and meant we preferred Williams," Beloussov added.
Sirotkin is heavily backed by the Russian bank-run SMP Racing programme.