LEGO Robotics Invention System 1.5 9747-1
LEGO Robotics Invention System 1.5 (9747-1) is worth about $207 on the secondary market today, against a $392 retail price. It has 717 pieces, belongs to the Mindstorms theme and was released in 1999. This set has retired — LEGO no longer produces it, so supply is fixed and prices are set entirely by the resale market.
- Set number
- 9747-1
- Theme
- Mindstorms
- Subtheme
- 1.5
- Year
- 1999
- Pieces
- 717
- Minifigures
- 0
- RRP
- $392
- Market value
- $207
- Used value
- $12
- Retirement
- Retired
Robotics Invention System 1.5 value by year
From $182 in 2011 to $182 in 2026 so far: +0%. Its highest year was 2024, at $190.
| Year | Value | Change |
|---|---|---|
| 2026 (so far) | $182 | −3.2% |
| 2025 | $189 | −0.9% |
| 2024 | $190 | +4.3% |
| 2023 | $182 | +0.0% |
| 2022 | $182 | +0.0% |
| 2021 | $182 | +0.0% |
| 2020 | $182 | +0.0% |
| 2019 | $182 | +0.0% |
| 2018 | $182 | +0.0% |
| 2017 | $182 | +0.0% |
| 2016 | $182 | +0.0% |
| 2015 | $182 | +0.0% |
| 2014 | $182 | +0.0% |
| 2013 | $182 | +0.0% |
| 2012 | $182 | +0.0% |
| 2011 | $182 | — |
Median of each year's market prices, sealed, in US dollars.
Frequently asked questions
How much is LEGO Robotics Invention System 1.5 (9747-1) worth?
LEGO Robotics Invention System 1.5 is worth approximately $207 on the secondary market today, based on current listings and completed sales. BrickStats updates this value daily.
Is LEGO Robotics Invention System 1.5 retired?
Yes — Robotics Invention System 1.5 (9747-1) has been retired by LEGO and is no longer in production. Retired sets have fixed supply, which is why their prices are driven purely by the resale market.
Has LEGO Robotics Invention System 1.5 gone up in value?
Not currently. Robotics Invention System 1.5 launched at $392 and trades around $207 today, 47.1% below its retail price. The price history chart shows the full trend.
What is the price per piece for Robotics Invention System 1.5?
At its $392 retail price across 717 pieces, Robotics Invention System 1.5 works out to about $0.547 per piece. Collectors often use price per piece to judge whether a set is good value.
Is LEGO Robotics Invention System 1.5 a good investment?
Robotics Invention System 1.5 currently trades 47.1% below its $392 retail price, and it is retired, so no new supply is entering the market. Past performance is not a prediction — condition, packaging and how long you hold all affect what a set actually sells for. BrickStats reports the numbers rather than giving investment advice.
Why is LEGO Robotics Invention System 1.5 so expensive?
Robotics Invention System 1.5 was released in 1999 and has since retired. Once LEGO stops producing a set, the only supply is what is already in circulation, so sealed copies in good condition compete for a shrinking pool of stock. That scarcity, not the parts, is what moves the price.