Is money earned from working at a company that deals in bribery unlawful, especially with the suspicion that spending a sum to buy an expensive watch for one of the managers of a client company is a bribe?

What the company pays to officials and managers of oil companies in exchange for their dealings with it is considered a prohibited bribe, regardless of the designation. The work of the questioner's sister in the company and her salary are permissible, but it is not permissible for her to disburse sums that she knows will be paid as bribes, due to the prohibition of assisting in giving bribes.