Each business day, TheStreet.com Ratings compiles a list of the top five stocks in five categories -- fast-growth, all-around value, large-cap, mid-cap and small-cap -- and publishes these lists in the Ratings section of our Web site.

For investors who prefer the diversification offered by mutual funds to owning individual stocks, here are some of the biggest holders of the companies that were on our list as of Thursday, Jan. 17.

DeVry ( DV):

( WPSRX) Westport Select Cap Fund allocated about 5.2% of its total portfolio as of Sept. 30, according to Thomson Financial.

( NSKAX) SunAmerica Focused Small-Cap Growth allocated about 3.2% of its total portfolio as of Dec. 31, according to the company's web site.

Heico ( HEI):

( RSDGX) RS Select Growth Fund allocated about 2.1% of its total portfolio as of Sept. 30, according to Thomson Financial.

( NBMIX) Neuberger Berman Small Cap Growth allocated about 1.7% of its total portfolio as of Sept. 30, according to the company's web site.

Bucyrus International ( BUCY):

( NBFSX) Neuberger Berman Fasciano allocated about 3.3% of its total portfolio as of Sept. 30, according to Thomson Financial.

( FSCGX) Fidelity Select Industrial Equipment allocated about 2.2% of its total portfolio as of Sept. 30, according to Thomson Financial.

Ametek ( AME):

( STRGX) Stratton Multi-Cap Fund allocated about 5.2% of its total portfolio as of Sept. 30, according to Thomson Financial.

( NMCGX) Nationwide Mid Cap Growth Leaders allocated about 4.2% of its total portfolio as of Dec. 31, according to the company's web site.

Woodward Governor ( WGOV):

( GSVIX) GE Institutional Small-Cap Equity allocated about 2.8% of its total portfolio as of Sept. 30, according to the company's web site.

( RYPRX) Royce Premier Fund allocated about 2.91% of its total portfolio as of Sept. 30, according to Thomson Financial.

For a description of the top five mid-cap stocks and an explanation of their ratings, click here .

Our quantitative rating is based on a variety of historical fundamental and pricing data and represents our opinion of a stock's risk-adjusted performance relative to other stocks.

However, the rating does not incorporate all of the factors that can alter a stock's performance. For example, it doesn't always factor in recent corporate or industry events that could impact the stock price, nor does it include recent technology developments and competitive dynamics that may affect the company.

For those reasons, we believe a rating alone cannot tell the whole story, and should be part of an investor's overall research.
This article was written by a staff member of TheStreet.com Ratings.