Your team reviews a lot of contracts. Yellow highlights mean 'definition or term'. Red means 'objection — needs negotiation'. Green means 'this clause is acceptable'. Blue means 'comment to the author'. New reviewers learn the code in five minutes and you save hours of explanation.
Flint supports colour-coded highlighting. The system is up to you.
Design the colour system first
Before annotating, agree on the meaning of each colour with your team. Write it down. Four colours is usually the sweet spot — more becomes hard to remember; fewer doesn't add much over single-colour. Common contract review system: yellow=term, red=objection, green=approved, blue=comment.
Apply consistently
Open annotate PDF, pick the highlight tool, set your first colour. Highlight all the items of that meaning. Switch colour, do the next meaning. Working colour-by-colour is faster than switching constantly. Recipient sees the pattern: clusters of red mean clusters of objections.
Document the legend
Add a sticky note on page 1 explaining the colour code. 'Yellow = definitions, red = objections, green = approved, blue = comments.' Reviewer opens the file, reads the legend, understands the markup in five seconds. Works even for recipients who weren't part of the original colour discussion.
Why colour beats text labels
Typing 'objection:' before every red comment doubles the visual noise. Colour communicates meaning at a glance. Reserve text for the content of the objection, not its category — that's the colour's job. Less typing, faster comprehension.
FAQ
Can I change a highlight's colour after applying?
Yes — select the highlight, change colour in the properties panel.
Do recipients see colours correctly?
Yes. PDF highlight colours are standard and render consistently across readers.
What if a reviewer is colourblind?
Add a text indicator (or use different shapes/strokes) as a secondary signal. Or share legend with colour names spelled out.
Can I filter highlights by colour?
Some readers (Acrobat) filter the comments panel by colour. Browser readers usually don't.
Pick four colours, mark consistently, save time. Colour-code highlights.