A Boarding Shield is a large tower shield comprised of ceramite and plasteel, which contains a small field generator similar to that utilised in the smaller wrist-mounted Combat Shield. These bulky shields are favoured by Space Marine assault units for protection. During the confined close quarter fighting of void combat boarding operations, Boarding Shields allows these assault units to absorb the sustained incoming enemy fire that normally accompanies the first breach in a voidship's hull. Boarding Shields were also employed by Space Marines during siege operations following the first breach in the defenses of a static fortification, when the heavy intensity of incoming enemy fire at close quarters created a combat environment similar to that of a voidship boarding action. The Boarding Shield was most often used during the Great Crusade and the Horus Heresy by the Space Marine Legions' Breacher Siege Squads.
- The Horus Heresy - Book One: Betrayal by Alan Bligh, pp. 70, 72, 112, 132, 204, 236
- The Horus Heresy - Book Two: Massacre by Alan Bligh, pp. 76, 99, 122
- The Horus Heresy - Book Three: Extermination by Alan Bligh, pp. 69, 88, 269
- The Horus Heresy - Book Five: Tempest by Alan Bligh, pp. 84, 86, 89, 110
- Forge World - Legion MK III Breacher Squad