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The origin of X-ray emission in Herbig Ae-Be stars comma intermediate-mass pre-main sequence stars comma is still disputed comma as these objects are not expected to be able to drive a dynamo to sustain magnetic activity. Their progenitors comma the intermediate-mass T Tauri stars openParIMTTSclosePar comma cover the transition from a convective core to a fully radiative one comma which is important for the presence of a magnetic field comma and thus their X-ray activity. At the same time IMTTS are still accreting from their protoplanetary discs comma which also contributes to their X-ray output. We have compiled a openParto our knowledge completeclosePar sample of 75 IMTTS comma and aim to compare their X-ray properties in relation to their masses comma ages and accretion rates. We apply for an XMM survey for 29 IMTTS to complete the sample coverage in X-rays.