Unfortunately not allowed in the line of work i chose. So now i use 50 different colored Post-It notes. Improvise, adapt and overcome.
If I may ask, what line of work are you in that prohibits the choice to use different colored pens?
I work in an office, so it’s sort of a silly rule. However, it does look more professional, and blue/black ink is just better for scanning/printing purposes.
I used to work for a CPA/professional auditor who advised me to keep purple pens on hand for original signatures. She did.
She said you’ll always be able to tell at a glance if you’re really the one who signed it, since almost no-one will have a purple pen around to fudge your signature. and no-one will kick up a fuss since it’s basically a blue pen.
Unless my grandma decides to go on a fraud spree. Purple’s her favorite color and the ONLY color she ever writes with.. so beware