WORKING PAPERS
-- NBER Working Paper No. 30829
-- https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4320887
Abstract: Rising market-to-book ratios may reflect off-balance-sheet intangibles, rents, or mispricing. Using U.S. firms 1974-2025, we estimate intangible depreciation from firm cross sections and define the valuation residual as market value beyond reproduction cost. Concentrated in large firms, it exceeds half their market value at dot-com and AI-era peaks. Among large technology firms, the dot-com peak reverses amid weak cash flows; the AI-era peak builds on stronger fundamentals. Higher residuals predict greater profitability and markups and coincide with weaker competition and lower investment-Q sensitivity, consistent with rents. They predict lower risk-adjusted returns only among small, low-profitability firms, arguing against pervasive mispricing.
(2) Green Products (with Po-Hsuan Hsu, Kai Li, and Joy Tianjiao Tong)
-- https://papers.ssrn.com/sol3/papers.cfm?abstract_id=5006863
-- 2025 AFA, 2025 FIRS, 2025 CICF, 2026 Baruch Climate Finance and Sustainability Conference
Abstract: We apply a novel text-based classification method to identify green trademarks that capture the commercialization of green innovation through products and services brought to market. Firms with more green products generate higher green revenues, emit less greenhouse gas, and receive higher environmental ratings. These firms also exhibit higher future firm value, especially when green products align with core businesses, prior experience, and product synergies. The valuation effect is driven by consumer environmental awareness rather than investor preferences or concerns. Consistent with a consumer demand channel, firms expand green product offerings following nearby natural disasters or peer firms’ environmental scandals.
(3) Greenhushing, Green Surfacing, and the Real Effects of the FTC's Green Guides (withb Kevin Tseng)
-- https://papers.ssrn.com/sol3/papers.cfm?abstract_id=7459421
--2026 Runner-Up Best Conference Paper Award, Alliance for Research on Corporate Sustainability (ARCS) Conference
--2026 Bocconi–Bristol Sustainability and Green Finance Workshop
Abstract: Environmental claims are easy to make and hard to verify. The FTC's 2012 Green Guides revision tightened the substantiation required for such claims, raising the value of claims firms can defend and the expected cost of claims they cannot. We measure green commercialization by applying large language models to the mandatory business description of 10-K filings, and compare consumer-facing industries, bound most strictly by the Guides, with other industries. The average effect is indistinguishable from zero, but the null masks opposite responses that hinge on ex ante credibility: previously unrated firms surface latent green activity, while firms with observably weak environmental ratings temper their claims. The same weak-rated firms compete on substance instead: green product patenting rises, and markup and gross profitability improve. Claims, once credible, are quickly imitated; verifiable products are not. A standard that makes green claims credible does not uniformly expand green commercialization; it reallocates green-market returns toward firms that respond on the investment margin.
(4) Green Entrepreneurship (with Po-Hsuan Hsu, Shenje Hshieh, and Geoffery Zheng)
-- https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6580538
--2026 FMA, 2026 HEC-HKUST-NUS Sustainable Finance Workshop
-- 2026 TFA / Excellence Award, Manulife Investment Bank x Aberdeen ESG-Sustainable Investment and Development Paper
Abstract: By constructing a comprehensive dataset of startups and their patenting and trademarking activities, we track the evolution and landscape of green entrepreneurship in the U.S. over the past four decades. We observe strong growth in the creation of green intellectual properties (IPs) by startups in aggregate: the proportion of startups with any green IPs increases from 2% in the 1980s to 7% in the 2010s. Specifically, the fraction of green patents (trademarks) filed by startups grew from 5% (2%) in the 1980s to 23% (5%) in the 2010s. We also observe significant cross-state variation in the growth of the proportion and count of startups with green IPs and startups having self-curated business profiles with high frequencies of environment-related keywords. We further examine how the surge of green entrepreneurship could be explained by education, policy incentives, and public attention to climate issues. We document significant increases in the number of green startups and the average startup's proportion of green IPs when (i) a green research institute is established in a local university, (ii) local community receives more green investment from the American Recovery and Reinvestment Act, and (iii) natural disasters impact neighboring counties.