I want to open a new business in Israel. I have found an investor ( a company) which is based in Israel and have jewish employees, some of them work on shabbos. Can I go with such investor? - my business wont require people to work on shabbos. - I am afraid that some of the work they do on shabbat might indirectly benefit to me.

It is permitted for you to go into a partnership with this investor, but you should add a clause to the agreement that you are not interested in any work done on Shabbat for your company, nor do you want any profit from work performed on Shabbat. Hashem should help that due to the positive relationship and friendship that will develop between you, they will be influenced and appreciate the importance of observing the Shabbat. (See Igrot Moshe, Orach Chaim 1, 91).