Roche Ireland, which is due to close its plant in Clarecastle by the end of 2018, spent 27.5 million euro on its staff last year.
The pharmaceutical giant made the huge investment in its workers on the same year that it announced plans to close it's Clare facility.
That move will cost the firm millions more.
Roche announced plans to close the Clarecastle plant last November, a move which will lead to the loss of 240 jobs.
The factory is set to shut by the end of 2018, leading to a massive economic blow for the area, and these figures go some way towards outlining just how big that will be.
Staff costs last year, including wages and salaries, totalled €27.5 million last year, up from €24.8 million a year earlier.
Roche Ireland Limited is reporting a 130 million euro loss for 2015, compared with a 9.6 million euro profit for the year before.
However, the loss is due to a writedown asociated with the closure.
The figures are contained in newly-filed accounts, which have been reported on by the Irish Times, and also show that nearly 4.5 million has been set aside as a provision for decommissioning the plant.
Talks aimed at securing a buyer ended without success earlier this year.
