Europe still needs GDS safeguards, despite changes in the market, lobby group C-FARE said.
The Brussels-based association said there is a "serious risk that full deregulation would not move the industry toward a more competitive structure, but rather would recreate the conditions that led to the current regulations."
It was replying to the recent EC Consultation paper of possible de-regulation, Distribution in the European Travel Market.
It added: "We believe the EU still needs a minimal set of clear, bright-line rules to constrain the kinds of anti-competitive behaviour that all in the industry know is inevitable for as long as there is airline ownership of CRSs."
The EC has called for another submission of views on de-regulation, to be sent in by April 27, following its last consultation in the Brattle Report of 2003.
But C-FARE said that despite the EC claims, "in reality nothing has substantially changed in the European CRS industry since Brattle."
During that time, the three major airline stake holders in Amadeus, Air France, Lufthansa and Iberia have reduced their holding in the GDS to, respectively, 23.2%, 11.6% and 11.6%.
But C-FARE said that the EC was also "minimising the extent of the market power of Amadeus and its airline owners in Europe."
It said the EC paper spoke Amadeus's "large" market share in Germany, France and Spain but claims that that country-by-country market shares are "confidential."
C-FARE said these are "widely available through MIDT data" and in 1995 amounted to 90% of all CRS bookings in Spain, 76% in France, 75% in Germany, 100% in Slovenia, 92% in Estonia, 93% in Lithuania, 96% in Latvia.
In the EU as a whole, Amadeus accounted for 55% of the bookings.
It also said the paper ignored "the threat of a double dominance in some countries of airlines and an airline-owned CRS that creates a particular potential for market foreclosure both for rival airlines and rival CRSs."
Neither, said C-Fare, did the paper mention the Air France/KLM merger, which has created Europe's number one airline not KLM plans to transfer to the same Amadeus reservations system used by Air France in 2007.
C-FARE stated: "We support the elimination of most of the provisions of the Code including the provisions that regulate pricing of CRS services to airlines but believe the core protections should be maintained for so long as there as large airlines in Europe remain owners of a large CRS."
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