# A Flexible Proof Format for SAT Solver-Elaborator Communication

arXiv: https://arxiv.org/abs/2109.09665 · HTML: https://mlsanity.com/paper/2109.09665/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 20 Sep 2021.

## Built on by (most cited first, 2 of 2)

- [Formally Certified Approximate Model Counting](https://mlsanity.com/paper/2406.11414/) (2024)
- [Efficient Certified Reasoning for Binarized Neural Networks](https://mlsanity.com/paper/2507.02916/) (2025)

## Abstract (arXiv)

We introduce FRAT, a new proof format for unsatisfiable SAT problems, and its associated toolchain. Compared to DRAT, the FRAT format allows solvers to include more information in proofs to reduce the computational cost of subsequent elaboration to LRAT. The format is easy to parse forward and backward, and it is extensible to future proof methods. The provision of optional proof steps allows SAT solver developers to balance implementation effort against elaboration time, with little to no overhead on solver time. We benchmark our FRAT toolchain against a comparable DRAT toolchain and confirm >84% median reduction in elaboration time and >94% median decrease in peak memory usage.