Direct proof of use
Amnesty International's 2017 arms-flow report identified DShK and DShKM heavy machine guns among the weapons used by all parties to the conflicts across Iraq and Syria, including Islamic State forces. That supports broad 2011 Syrian Civil War use rather than a single-side-only claim.
Business Insider, summarizing IHS Jane's reporting from U.S. Federal Business Opportunities documents, reported that December 2015 U.S. shipments to Syrian rebels included a 27,006-pound combined AK-47 and DShK package and a separate 7,903-pound DShK and RPG-7 package. That source supports transfer or supply to opposition forces, while the Amnesty report supports fielded use across the wider Syria/Iraq conflict environment.
Sources: Amnesty Iraq Turning a Blind Eye, Business Insider US Arms to Syrian Rebels
Timeline
Conflict Armament Research documented weapons captured from Islamic State forces in northern and north-eastern Syria in mid-2014, showing the Islamic State battlefield materiel context around Ayn al-Arab and Ras al-Ayn. The CAR dispatch does not list a DShK in the extracted case summaries used here, but it anchors the Islamic State captured-weapons context in the same Syrian theater.
By December 2015, U.S.-documented supply packages to Syrian rebels included DShK heavy machine guns in combination with AK-47s and RPG-7s. In January 2017, Amnesty's report placed DShK and DShKM heavy machine guns in use by parties across Iraq and Syria, including Islamic State forces.
Sources: CAR Islamic State Weapons in Iraq and Syria, Business Insider US Arms to Syrian Rebels, Amnesty Iraq Turning a Blind Eye
Battlefield role
In Syrian Civil War use, the DShK's documented role was heavy machine-gun fire support from crew-served positions, technicals, and other improvised or vehicle-mounted arrangements. Amnesty treated DShK and DShKM guns as part of the small-arms and light-weapons mix in Iraq and Syria, while the U.S. shipment reporting placed the type in opposition supply packages rather than as a new locally produced weapon.
The role package for this record is therefore fire support, limited air defense, and irregular-force use. The available public sources support fielding by multiple sides, but they do not provide a complete incident-by-incident firing log or reliable counts of DShK guns held by each faction.
Sources: Amnesty Iraq Turning a Blind Eye, Business Insider US Arms to Syrian Rebels
Side attribution
The strongest source-backed side statement is multi-party use. Amnesty's formulation covers all parties across Iraq and Syria and explicitly includes Islamic State; the parent catalog row therefore includes Syrian government and allied forces, opposition and anti-government forces, Syrian Democratic Forces and coalition partners, and Islamic State or jihadist groups.
The opposition-side transfer claim is more specific: Business Insider's IHS Jane's-based article ties DShK shipment bundles to Syrian rebels in December 2015. The CAR dispatch provides Syrian-theater Islamic State weapons context, but it is used here as contextual support rather than as a direct DShK identification.
Sources: Amnesty Iraq Turning a Blind Eye, Business Insider US Arms to Syrian Rebels, CAR Islamic State Weapons in Iraq and Syria