Ulster chief executive Michael Reid is waiting for the Dragons to give specific details of alleged racist abuse during the Celtic League clash at Ravenhill last Friday night.
The Dragons management have said Colin Charvis and Aled Brew were racially abused by Ulster fans during the first half of the match and Reid has promised to take the allegation "extremely seriously."
However, having reviewed footage of the match Ulster have been unable to identify any such abuse and will ask the Dragons to clarify their complaint before investigating the matter further.
"We are still awaiting specific details from the Dragons as to what exactly they are alleging took place at Ravenhill on Friday night," Reid said, "and until we have that information we cannot fully investigate the matter.
"We have, however, spent some time over the past couple of days looking at tapes of the match and CCTV footage from the ground and have yet to identify anything untoward, however we will revert to the Dragons in due course.
"There is no doubt that if it is proven that anything of a racist nature has been said to any of the opposition players we will take this extremely seriously as this sort of behaviour has no place in Ulster rugby."
