Professor Oak's New Theory

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

$6.99
Reverse Holofoil · Market price ▲ 0.4% (30d)
Prices as of Oct 21, 2026
SupporterArt · Ken Sugimori
33graded pop
9%gem rate
63.5×PSA 10 vs raw
-63%off ATH $1.93 · Jul 2025
−$6.88EV to grade — don't
Market data

Printings & price history

Reverse Holofoil▲ 0.0% 7d$6.99
Low $4.00Mid $14.08

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Graded market

Graded values

updated 2026-10-21
Grade 6 est.$5.50
Grade 5 est.$4.63
Grade 4 est.$3.82
Grade 3 est.$3.18
Grade 2 est.$2.61
Grade 1 est.$2.20

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

Reverse Holofoil · Ungraded price history$5.79

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

Graded population census · updated 2026-09-17

Reverse Holofoil
CGC9 graded · 0 gem 10
PSA3 graded · 0 gem 10

Population data from PriceCharting, updated monthly.

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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 $0.72 ungraded. Across the 2 printings we track, copies run anywhere from $0.25 to $62.86 depending on the version you're holding.

Grading changes the math on this one: a PSA 10 is valued around $45.73, roughly 63.5x the raw price, while a PSA 9 sits near $16.15. 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→