the transient is therefore fully consistent with a nuclear origin.

An alternative astrometric constraint can be obtained using the [*Gaia*]{} Science Alerts (GSA) detections [@Hodgkin2013]. Gaia19eks was discovered at a separation of 38 milli-arcseconds (mas) from the reported location of its host galaxy in [*Gaia*]{} data release 2 (GDR2; @Gaia2018). The estimated astrometric uncertainty of GSA is $\sim$100 mas [@Fabricius2016], and the coordinate systems of GSA and GDR2 are well aligned [@Kostrzewa2018; @Wevers2019b]. This measurement corresponds to an even tighter constraint on the offset of $12\pm32$pc.

*Swift* UVOT data
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Target-of-opportunity observations spanning 39 epochs (PIs Yu and Nicholl) were obtained with the UV-Optical Telescope (UVOT) and X-ray Telescope (XRT) on-board the Neil Gehrels Swift Observatory (*Swift*). The UVOT light curves were measured using a $5''$ aperture. This is approximately twice the UVOT point-spread function, ensuring the measured magnitudes capture most of the transient flux while minimising the host contribution (the coincidence loss correction for the UVOT data is also determined using a $5''$ aperture, ensuring a reliable calibration of these magnitudes). The count rates were obtained using the *Swift* <span style="font-variant:small-caps;">uvotsource</span> tools and converted to magnitudes using the UVOT photometric zero points [@Breeveld2011]. The analysis pipeline used software HEADAS 