Professor Oak's New Theory

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

$0.75

Market price ▼ 8.5% (30d)

Prices as of Sep 30, 2026

Normal Reverse Holofoil

SupporterArt · Ken Sugimori

45graded pop

7%gem rate

55.8×PSA 10 vs raw

-61%off ATH $1.93 · Jul 2025

−$9.31EV to grade — don't

Market data

Printings & price history

Normal▲ 1.4% 7d$0.75

Low $0.25Mid $0.75

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Graded market

Graded values

PSA 10 report →updated 2026-09-30

Grade 6 est.$0.71

Grade 5 est.$0.60

Grade 4 est.$0.50

Grade 3 est.$0.41

Grade 2 est.$0.34

Grade 1 est.$0.29

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$41.82

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

Graded population census · updated 2026-09-17

PSA18 graded · 2 gem 10

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CGC15 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 $0.75 ungraded. Across the 2 printings we track, copies run anywhere from $0.25 to $62.96 depending on the version you're holding.

Grading changes the math on this one: a PSA 10 is valued around $41.82, roughly 55.8x the raw price, while a PSA 9 sits near $14.63. 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.

Collecting HeartGold & SoulSilver?Full master set guide — every card, chase list, and completion cost→