Yes, I would this if I was uncomfortable with sharing it and when she asks when you are coming in the use the light table then tell her you already copied the pattern at home. If she then keeps asking you for the pattern tell her you are not comfortable with sharing it because of copy right laws. Is part of the reason too because she did not offer to buy the pattern with you or offer to pay half the cost of the pattern? Also are you sure she wants to copy the pattern or is she wanting to help you like some one mentioned. I think the key is how you feel about it and how you interpet copy right laws. I took how you described it that she just wanted to copy the pattern for herself.
Originally Posted by hobo2000
The fact that you are using the light table at her workplace puts you in untenable situation. Stay home and copy it on a window facing the sun.