Is it legal for an employer to only match 401k contributions for select employees?

I have noticed in an anual report that the fund grew by a certain dollar figure. The dollar figure was broken down by employee contributions and invesment growth, but the total growth was more than the sum of the two expected growths. The company as a whole has been told there is no employer match, but that addiional income to the fund had to come from somewhere??

how would i look into it further without potentially getting fired?

You need to look into your 401k Summary of Plan , normally you get this when you first sign up for the 401k or ask your HR/Payroll department. Some employers offer matching up to a certain percentage of your contribution and of your annual income. Some also offer employer discretionary matching/profit sharing. If this is the case not all employees may get extra money put into their account from the employer. The Plan Summary will be able to tell you what the employer contributions are and who is eligible for them. Also on the annual report their may be another piece of employee contributions that aren't listed, like rollovers from other accounts. To summarize your best bet is to get a hold of the summary plan and review it for employer contributions or just ask HR/Payroll to help you understand the report.

No, that is a violation of ERISA laws. you should look further into the situation.

were dividends included in the "investment growth"? that might be the extra.