Baidu's AI line grew 25 percent and still lost the arithmetic

Baidu reported second-quarter revenue of RMB31.3bn ($4.62bn), down 4 percent year on year and 2 percent on the prior quarter, its fifth consecutive quarterly decline ^[1]. The number worth studying is not the AI growth rate, which is high, but the subtraction underneath it: the AI segment grew 25 percent and still did not fill the hole the ad business dug ^[2][4].

Run it. Online marketing, the legacy mainstay, fell 19 percent to RMB13.1bn ^[2], which implies roughly RMB16.2bn a year earlier and about RMB3.1bn of revenue simply gone ^[1]. The Core AI-powered Business came in at RMB12.5bn, up 25 percent ^[4], implying a base near RMB10bn and a gain of about RMB2.5bn ^[2]. The new business therefore replaced roughly 80 percent of what the old one lost ^[3]. To hold revenue flat, that AI line would have needed to grow about 31 percent, not 25 ^[4]. Group revenue fell about RMB1.3bn ^[5]. Reuters attributed the ad decline to a weak Chinese property sector and cautious consumer spending, both of which have pushed companies to cut marketing budgets ^[3].

This is the standard shape for a portfolio funding a new bet out of a declining cash cow. Fast percentage growth on the smaller base loses to slower percentage decline on the bigger one until the two bases cross, and Baidu's have only just met: the AI segment is now half of general business revenue ^[4]. Until the crossover, headline growth rates flatter. GPU Cloud, the accelerator rental line, rose 283 percent, accelerating from 184 percent the quarter before ^[6], and Baidu renamed it this quarter from "subscription revenue from AI accelerator infrastructure" ^[7]. AI Cloud Infra rose 50 percent to RMB7.3bn ^[5], a gain of about RMB2.4bn that accounts for nearly all of the AI segment's increase ^[10].

The cost side is the other half of the arithmetic. Excluding iQIYI, capital expenditure tripled to RMB11.4bn from RMB3.78bn, Bloomberg reported ^[11]. The increase alone, about RMB7.6bn ^[8], is roughly three times the AI revenue gain it bought ^[9]. Capex ran about 3.4 times operating cash flow of RMB3.4bn ^[12][6] and about five times net income, which fell to RMB2.3bn from RMB7.3bn, a drop Bloomberg put at 68 percent ^[8][7]. Baidu has RMB283.1bn in total cash and investments to absorb that ^[12] and has returned $259mn through buybacks since January ^[13]. Tencent reported this month that its own AI compute bill outgrew its cash flow ^[14].

The spending has not yet bought a leading model. Ernie has gone months without a major upgrade, Reuters reported ^[15], and Bloomberg wrote that it now trails open-weight models such as Moonshot AI's, which match OpenAI and Anthropic on key benchmarks ^[16]. Chief executive Robin Li told analysts Baidu would return Ernie to the frontier, saying competitiveness "ultimately comes down to sustained technology investment, application-driven approach, and patience" ^[17]. The market was less patient: shares fell as much as 10 percent to $93.70 according to Bloomberg, with Reuters reporting a 7 percent early slide, against a Bloomberg-poll consensus of RMB31.6bn cited by the South China Morning Post ^[9][10]. Apollo Go, the robotaxi unit, is in 28 cities with more than 350mn autonomous kilometres logged ^[18].

Watch the two growth rates, not the segment mix. The ad decline has to decelerate or the AI line has to clear about 31 percent for group revenue to stop falling ^[4], and the capex-to-operating-cash-flow gap sets how long the crossing can be financed ^[6].