Leaders Cork Constitution were held 3-3 at Anglesea Road by Old Belvedere. In a game played in terrible conditions, Josh Glynn put Belvo' ahead early in the second half but Jonathan Holland levelled for Con' shortly after.
Defending champions Lansdowne won their first game of the campaign defeating Young Munster 29-22 on the back pitch in the Aviva Stadium. Munster's led 13-7 at half time with a try from Brian Haugh who also added a conversion and two penalties. Three second half penalties by Haugh secured a losing bonus point.
Clontarf had a deserved 21-15 victory over Dolphin at Musgrave Park. Two tries on the half hour mark by Michael McGrath and Max McFarland both converted by David Joyce set the visitors on the way to victory.
A penalty from Barry Keeshan left it 14-3 to 'Tarf at half time. A try eight minutes into the second half closed the gap but a third try mid way through the half by Colm O'Shea converted by Joyce ended the game as a contest.
Dolphin rallied in the closing stages and a try by John Gleeson converted by Gleeson secured a bonus point for the home side.
Both Shannon and U.L. Bohemian recorded wins in Division 1B.
Shannon defeated Dungannon 17-6 at Coonagh to get their first win. Duncan Casey and Luke O'Dea scored tries for the home side and Tadhg Bennett converted both and also added a penalty.
U.L. Bohemian picked up maximum points in their 31-6 away win over Malone. Rory White scored two tries for the winners and Eoin Sweeney, John Sutton and Adrian Enright were the other try scorers for the Limerick side. Tim Rafferty kicked three conversions.
U.C.C. won the Cork derby under lights at the Mardyke with a 15-7 victory over Highfield in Division 2A. Joe Holland and Peter McCabe scored tries for the students and Steve Dinan added a conversion and a penalty for a 15-0 interval lead. Kevin Foyle replied with a try for Highfield late in the second half and Ian O'Donoghue converted.
Elsewhere in this Division, Bruff, Old Crescent and Cashel all lost at home. Rainey Old Boys defeated Old Crescent 38-20, Cashel were defeated by Galwegians 19-14 and Bruff were just edged out by Bective Rangers 10-9 at Kilballyowen Park.
Nenagh Ormond remain on top in Division 2B after they defeated bottom side Sunday's Well 20-7.
Thomond won the big Limerick derby in front of a large crowd at Liam Fitzgerald Park with a 19-13 victory over Richmond.
A try from Eamon Ronan and two penalties by Christopher Walker helped Midleton to an 11-9 home win over Suttonians.
Ulster Bank League Division 1A: Dolphin 15, Clontarf 21;
Garryowen 11, U.C.D. 25;
Lansdowne 29, Young Munster 22;
Old Belvedere 3, Cork Constitution 3;
St. Mary's College 15, Ballynahinch 9;
Division 1B: Belfast Harlequins 12, Terenure College 13.
Blackrock College 5, Galway Corinthians 27;
Dublin University 7, Buccaneers 15;
Malone 6, U.L. Bohemian 31;
Shannon 17, Dungannon 6;
Division 2A: Bruff 9, Bective Rangers 10;
Cashel 14, Galwegians 19;
City of Derry 30, Naas 14;
Old Crescent 20, Rainey Old Boys 38;
Old Wesley 23, N.U.I.M. Barnhall 11;
Queens University 12, Ballymena 15;
Seapoint 19, Banbridge 13;
U.C.C. 15, Highfield 7;
Division 2B: Ards 20, D.L.S.P. 14;
Boyne 20, Instonians 18;
City of Armagh 32, Tullamore 9;
Greystones 41, Sligo 15;
Midleton 11, Suttonians 9;
Navan 9, Skerries 16;
Nenagh Ormond 20, Sunday's Well 7;
Thomond 19, Richmond 13;