MK-V at Healdsburg, California, USA (Foxhill Vineyard)

Monarch Tractor (founded 2018, Livermore, California; founder and CEO Praveen Penmetsa) built the MK-V, a fully battery-electric, driver-optional smart tractor with a WingspanAI fleet-management and remote-supervision layer. The registry records it at commercial maturity to reflect a genuine historical peak: the MK-V shipped to paying commercial customers starting in December 2022, the first being Constellation Brands, which took six tractors for its To Kalon vineyard, following an earlier 2021 pilot at Wente.

Monarch raised more than $220 million (some reports up to roughly $251 million), anchored by a $133 million Series C in July 2024. The lifecycle state is discontinued, recording a major correction to the originating dispatch's framing of an active, growing manufacturer: Monarch collapsed through 2025, with its Foxconn manufacturing arrangement ending when the Ohio plant was sold to SoftBank in August 2025, layoffs and a shutdown warning in November 2025, a pivot to roughly 70 percent licensing revenue, and finally an assignment for the benefit of creditors.

Its assets and intellectual property, including the software-defined vehicle platform and perception stack, were acquired by Caterpillar around April 14, 2026, in an asset and technology purchase with undisclosed terms rather than a going-concern acquisition. On autonomy, marketing of a fully autonomous tractor overstated reality: full autonomy was confined to a narrow dairy feed-pushing use case in outdoor feed lanes, while general field work was driver-assist with an operator aboard, and an Idaho dealer sued in September 2025 alleging the tractors could not operate autonomously, with Monarch's sales team reportedly conceding the limits in writing.