Scantegrity

However, the correctness of each of these tallies requires the voter to either trust that the software is error-free and has not been hacked, or that the physical chain-of-custody of the ballots has not been broken at any point.

[2] Other E2E voting systems such as Punchscan and ThreeBallot, address these issues but require existing polling place equipment and procedures to be greatly altered or replaced.

[3] In contrast, Scantegrity is an add-on meant to be used in conjunction with existing optical scan equipment, thereby requiring fewer hardware and software and procedural modifications.

Similarly, the underlying system still produces both an electronic tally as well as a human readable paper trail through which manual recounts can still be conducted.

[4] The voter marks the location using a specially provided "decoder" pen, which activates the invisible ink causing it to darken, revealing a confirmation code.

[5] Voters wishing to verify that their vote is unmodified may write down the confirmation codes for each race on a detachable chit that contains the ballot's serial number.