use of spot models. Star spot occultations have been seen in the transit light curves of several planets, including HD189733b (@Pont2007; @Sing2011), TrES-1b (@Rabus2009; @Dittmann2009), CoRoT-2b (@Wolter2009; @Huber2009; @Silva-Valio2010), HAT-P-11b (@Sanchis-Ojeda2011_hat11; @Deming2011; @Beky2014_hat11), WASP-4b (@Sanchis-Ojeda2011_wasp4; @Hoyer2013), WASP-19b (@Mancini2013; @Reed2013; @Huitson2013; @Mandell2013; @Sedaghati2015), HATS-2b [@Mohler2013], Kepler-63b [@Sanchis-Ojeda2013], Qatar-2b [@Mancini2014], and HAT-P-36b [@Mancini2015].

If a planet occults a spot (a region cooler than the surrounding photosphere) it blocks less of the stellar flux than compared with its transit across the hotter pristine stellar disc. This results in a bump during transit and therefore a smaller derived planetary radius. Star spot activity is not unexpected for WASP-52 since [@Hebrard2013] found modulations in its light curve and chromospheric emission peaks in the CaII H+K lines. Using these modulations they calculated the rotation period of WASP-52 to be 16.4 days.

![image](wasp52_fit_ma.pdf)

Spot crossing events have been modelled with a variety of techniques, such as <span style="font-variant:small-caps;">prism</span> [@Reed2013], <span style="font-variant:small-caps;">soap-t</span> [@Oshagh2013] and <span style="font-variant:small-caps;">spotrod</span> [@Beky2014]. For this analysis we used <span style="font-variant:small-caps;">spotrod</span> to generate the spot affected light curves and wrote an MCMC wrapper around these generated light curves to fit them simultaneously across the bands and with the same long time-scale trends as before. We 