In response to the public LIGO/Virgo gravitational wave (GW) alert of the on-going osservative run O3, with trigger event name S190521r at T0 = 2019-05-21T07:43:59 (UT), the AGILE Team performed a quick look follow-up analysis of the AGILE data.

Preliminary AGILE-MCAL and AGILE-GRID upper limits have been published in two GCN CIRCULARS:
GCN #24636: LIGO/Virgo S190521r: No counterpart candidate in AGILE-MCAL observations (C. Casentini et al.)
GCN #24638: LIGO/Virgo S190521r: Upper limits from AGILE-GRID observations (F. Verrecchia et al.)