How a move earns its place on the board.

We publish a move only when we can point to sources for where the scientist landed, and in almost every case where they came from and when. Not all sources carry the same weight.

Evidence tiers

Tier A

Straight from the people involved: the scientist’s own statement, or an announcement from either institution.

Tier B

Reporting from established outlets with named sources.

Tier C

Databases like OpenAlex and ORCID. They help confirm a move, but we never publish one on database evidence alone.

Every published record lists the sources behind it, so you can check our work.

We never guess why someone moved. A record gets a reason tag only when the scientist gave one publicly, and the tag quotes or links what they said: stated policy reasons, stated mixed reasons, or stated non-policy reasons. Most records carry no reason tag at all, because most scientists never say.

The board follows senior scientific talent, so every scientist on it gets a distinction tier.

Distinction tiers

Tier 1

Global Laureate. Winners of the Nobel Prize, Fields Medal, Abel Prize, Breakthrough Prize, Turing Award, and awards of comparable standing.

Tier 2

Internationally Decorated. Winners of major international prizes and national-academy-level honors a step below Tier 1.

Tier 3

Research Leader. Institute directors, endowed chairs, and scientists whose move matters for their field.

Records are grouped into transfer windows, most of them aligned to academic years. When we have researched a window in both directions, scientists joining the US and scientists leaving it, we call it comprehensive and show summary numbers for recorded moves, like net flow. This means research in both directions, not an exhaustive count or equal discovery of every move. A selected window collects notable moves only, so we show the records without totals that would understate the real picture.

The US inbound and outbound counts include only real changes of primary affiliation that cross the US border. Net flow is simply inbound minus outbound.

Scientist profiles include a career timeline drawn from public records, largely via OpenAlex. That timeline is there for context. It is not a list of transfers, and it never feeds the board’s numbers. Only records verified through the process above do.

The historical explorer uses published aggregates from the Scholarly Migration Database 2026 V2, by Tom Theile, Aliakbar Akbaritabar, and Emilio Zagheni at the Max Planck Institute for Demographic Research. It is licensed CC BY 4.0. Each chart links to the source release, and the explorer provides downloadable country data.

These estimates infer movement from changes in the affiliations researchers list on journal articles and reviews. The method chooses the most frequent location for each researcher and year, handles multiple affiliations, and fills some publication gaps using up to two subsequent years. It measures publication-affiliation changes, not citizenship, and publication delays affect the dates.

Historical counts cover 1998–2024. In this release, population denominators and rates are available only through 2021, and bilateral country flows stop in 2022. We preserve those limits. Missing values never become zero or a complete period average. Rates use the source population for the same year and field, scaled to 1,000 researchers.

OpenAlex and Scopus differ in coverage and author identification. Their estimates can differ substantially, even in the direction of net migration. Readers can switch between them. These populations are different from our editorial selection of verified senior-scientist moves, so we never join the series or treat their totals as directly comparable. A change over time does not establish its cause.

Spotted an error? Email contact@ffppod.com with a source and we will review it. Every record shows when it was last verified, so corrections are visible, never silent.