The commission, which is under the Ministry of Trade and Industry, issued a Proposed Infringement Decision yesterday to the agencies, which include respected names like Avenue Management, Diva Models and Mannequin Studio.
They are suspected of collectively raising rates for various modelling services, in breach of the Competition Act.
A CCS spokesman said investigations began in 2009, after the commission received a complaint from a modelling agency that is not among the 11.
"CCS' investigations revealed that the price-fixing activities commenced in 2005, when the said modelling agencies coordinated to collectively raise rates," said the spokesman, noting that the price-fixing activities were terminated after CCS commenced investigations in 2009.
Each of the 11 agencies has until May 30 to submit responses to the commission.
Mr Chris Swee, general manager of Looque Models Singapore, one of the affected agencies, said his agency is seeking legal advice. He added that "no hard and fast rule" exists for prices.
Modelling rates have indeed been rising. Independent stylist Vik Lim noted that, in the last three years, editorial rates - fees that modelling agencies charge for a magazine or newspaper photo shoot - have "been raised from about $600 a day to $800 a day".
However, he believes the higher rates will "create a better industry in Singapore for models". Mr Justin Lim, director of Style House modelling agency, which is not among the 11 listed, feels that models in Singapore are "grossly underpaid".
In Malaysia, for example, models are paid around US$30,000 (S$37,300) to appear in a TV advertisement. In Singapore, they are paid between $800 and $5,000 for the same work, he said. But he added that "price fixing is unfair to clients".
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