I did this for a highy advanced race passing down to a lower tech race. I had the option for tech transfer turned off but that did not prevent tech transfer
23 technologies were transferred in an inconsistant pattern for instance capacitor recharge rate 3,4.5, and5 were transferred and source race had 6 and I thinl the reciever already had 3 , they go 12 and 30 cm lasers as well but nothing inbetween
edit It also looks like I can build the captured ships despite their individual components being beyond the capturing race