Professor Oak's New Theory

HeartGold & SoulSilver · #101/123 · Uncommon · 2010

$0.90

Market price ▲ 0.0% (30d)

Prices as of Jul 26, 2026

Normal Reverse Holofoil

SupporterArt · Ken Sugimori

42graded pop

7%gem rate

7.5×PSA 10 vs raw

-23%off ATH $1.93 · Jul 2025

−$10.75EV to grade — don't

Printings & price history

Normal▲ 0.0% 7d$0.90

Low $0.25Mid $0.78

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Graded values

updated 2026-07-26

Grade 6 est.$1.42

Grade 5 est.$1.19

Grade 4 est.$0.98

Grade 3 est.$0.82

Grade 2 est.$0.67

Grade 1 est.$0.57

Grades 1–6 are estimates modeled from the raw price — PSA/CGC/BGS 7–10 and Ungraded are live tracked market values.

PSA 10 price history$52.22

PSA 10 chart is building — graded values are tracked nightly, a new point appears each day.

Graded population census · updated 2026-07-08

PSA18 graded · 2 gem 10

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CGC12 graded · 1 gem 10

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Population data from PriceCharting, updated monthly.

How much is Professor Oak's New Theory #101/123 worth?

Professor Oak's New Theory #101/123 is a Uncommon card from HeartGold & SoulSilver (2010) — today it trades at roughly $0.90 ungraded. Across the 2 printings we track, copies run anywhere from $0.25 to $63.10 depending on the version you're holding.

Grading changes the math on this one: a PSA 10 is valued around $52.22, roughly 58.0x the raw price, while a PSA 9 sits near $18.78. 18 copies have been graded to date, and 11% of them came back a 10 — worth knowing before you pay grading fees.

These figures come from nightly market-data syncs verified against completed sales. Use the chart above to see the trend before you buy or sell.