(Reuters) -- Goldman Sachs Group has suspended coverage of 18 discount brokers, exchanges and small investment banks because the analyst who follows them has left the firm.

The company told clients in a research note on Friday that Dan Harris, a vice president who covered Jefferies Group, Lazard, Stifel Financial, CME Group and 14 other companies, has left the firm. It did not give a reason for his departure but said coverage of the companies would be suspended pending reassignment to a new analyst.

Harris joined Goldman in late 2006 and previously was an associate analyst covering securities firms, asset managers and market structure at JPMorgan Chase. Calls to his office were referred to a Goldman spokeswoman, who declined to comment.

Goldman, along with the rest of Wall Street, has imposed widespread layoffs in recent months as companies battle weak markets, a slow economic recovery and new regulations constricting their proprietary trading and investment capabilities.

Goldman has fired more than 1,000 employees in recent months across all levels of seniority and specialties, coupled with the early "retirement" of a high number of high-level executives known as managing directors-partners at Goldman.

The company spent about $250 million in severance costs in 2011, including about $50 million in the last quarter of the year, chief financial officer David Viniar said in January.

The firms followed by Harris are:

CBOE Holdings, CME Group, Intercontinental Exchange, Knight Capital Group, MarketAxess Holdings, Nasdaq OMX Group, NYSE Euronext, TD Ameritrade, Duff & Phelps, E*Trade Financial Corp, Greenhill & Co, Jefferies, Lazard, LPL Investment Holdings, Raymond James Financial, Stifel Financial Corp, Charles Schwab and Evercore Partners.

(Reporting By Jed Horowitz; Editing by Tim Dobbyn)