Reckitt Benckiser (RB) confirmed the plastic bottles were used for the stain removal product Vanish.
Bottles started arriving at Poldhu Cove on the Lizard on Sunday before more arrived at Porthleven on Friday.
The firm said the bottles came from a container lost at sea off a ship in 2015.
RB said it was "providing all the agencies involved in the clear up with logistical and financial support".
Volunteers and staff from Culdrose Naval Air Station carried out another clean up on Friday at Poldhu beach.
Cornwall Council said 18,720 bottles were being transported in the container, of which approximately half have already been accounted for.
It is thought the vessel lost the container near Land's End in May.
A global firm has admitted responsibility for thousands of pink bottles washing up around the coast of Cornwall.