The FAI say it has received a letter from St Patrick's Athletic in relation to UEFA Club Licensing and they are looking into the matter.
In a statement released this evening, the FAI said: "The Football Association of Ireland can confirm it is in receipt of a letter from St Patrick’s Athletic in relation to UEFA Club Licensing and is looking into the matter."
St Pat's finished fifth in last season's SSE Airtricity Premier Division table, with Waterford claiming the last of the three Europa League spots.
It is believed St Pat's are questioning Waterford's eligibility for European competition.
If Waterford were not granted a UEFA licence then St Pat's would be next in line.