Three Pillars
Tax
Why did Apple's effective tax rate sit at 12-16% for years? How does the OECD Pillar Two global minimum tax change Big Tech's earnings? I read the 10-K income tax footnote the way practitioners do, and decode it for you.
US Stocks
The blind spots for non-US investors: the USD 60,000 estate tax threshold, ADR dividend withholding, after-tax returns that differ by fund domicile. Cross-border details most finance content never touches.
AI Automation
Automating investment research with Python, SEC EDGAR, and AI tools: 13F tracking, deep-reading filings, multi-source verification against hallucination. Methods fully public, so you can build your own.
Articles in English
Taiwan's 183-day rule: when foreigners become tax residents, and what happens to offshore investments
How the days are counted, the four-step legal chain that pulls offshore income into Taiwan's minimum tax at 183 days, and the three details expats miss.
The most dangerous tax for foreign investors in US stocks: the USD 60,000 estate tax threshold
US citizens get a USD 15M exemption; nonresident aliens get USD 60,000. What counts as US-situs, the correct computation, and three planning routes.
TSM ADR vs the Taiwan-listed share: the two tax questions most people get wrong
Is the 21% dividend withholding recoverable? Is a TSM ADR a US-situs estate tax asset? The issuer test settles both.
Apple's tax code, decoded: ETR spiked from 12% to 24%, then settled at 15.6%
Five years of effective tax rate in one read: four structural drivers, the USD 10.2B EU State Aid one-off, and the new normal under Pillar Two.
About Jeff
20+ years in international tax. BA in Accounting, MS in Accounting, MS in Finance. Specialized in OECD Pillar Two / GloBE and cross-border tax structuring. Also a hands-on US stock investor who automates his own research with Python and AI tools.
This site covers what I want to read but cannot find: the intersection of tax expertise and US stock investing, plus the AI workflow that automates it all.