Markel (NYSE:MKL) may be one of the most promising long-term-oriented financial holding companies the stock market has to offer, but recent SEC filings from the company reveal that not everyone should be buying more shares right now, says Fool contributor Steve Symington in the following interview with the Fool's Alison Southwick.

Specifically, Markel employees currently own a significant chunk of Markel in their own retirement accounts -- in fact, Markel common stock represents more than a quarter of the total value of all investments in the company's retirement plan.

But what do you think? Are Markel employees' retirement holdings dangerously overexposed to their company's stock, or are they wise to put so much of their nest eggs in one basket? Please watch the video to get Steve's full take, and weigh in using the comments section below.