I work in a non-Muslim country and I have a company in which some non-Muslim people work. Can I buy some gifts to display in the company in acknowledgement of Christmas and as a token of participation on my part with them, or is this haraam?

Praise
be to Allah.

It is not permissible to participate in Christmas festivities by offering
gifts, taking time off work, putting up decorations, and the like. It is
also not permissible to offer congratulations on the occasion of these
festivals, because they are innovated and haraam festivals that are
connected to corrupt beliefs. Moreover, celebrating them is an imitation
of the Christians, and that is emphatically haraam, because the Prophet
(blessings and peace of Allah be upon him) said: “Whoever imitates a
people is one of them.” Narrated by Abu Dawood (4031); classed as saheeh
by al-Albaani in Irwa’ al-Ghaleel (5/109) 

See also the answers to questions no. 947 and
12866 

And Allah knows best.