OpenPath

The Trade Desk's proprietary direct-to-publisher supply path, competing with traditional SSPs for a share of the programmatic supply chain

OpenPath is a supply-path optimization (SPO) initiative launched by The Trade Desk in February 2022, designed to give TTD's demand-side platform direct access to premium publisher inventory through Prebid.org's open-source header bidding framework. By integrating directly with publishers, OpenPath allows The Trade Desk to bypass traditional supply-side platforms (SSPs) in certain transactions, reducing intermediary fees and improving bid transparency, data fidelity, and auction efficiency for both buyers and sellers. The initiative was positioned as a response to growing industry concerns about supply chain opacity and the proliferation of SSP middlemen taking margin without adding clear value. OpenPath enables The Trade Desk to receive first-look access to publisher inventory, pass more accurate signals to its bidding algorithms, and offer advertisers cleaner, more accountable supply paths. Publishers who integrated OpenPath gained direct demand from one of the largest DSPs in the world, theoretically improving yield and reducing latency. However, OpenPath has faced significant headwinds. By 2025, a number of publishers began pulling back from the integration amid concerns about auction quality, bid shading practices, and the broader power dynamics of a major DSP having direct, unmediated access to their inventory. Critics raised questions about whether OpenPath's auction mechanics disadvantaged publishers relative to SSP-mediated paths. Despite these tensions, OpenPath remains an active and strategically important component of The Trade Desk's supply-chain strategy and its broader effort to reshape the programmatic ecosystem.