Short answer
A replica Patek Philippe is a watch built to copy a Patek Philippe model. Many replicas also carry the Patek Philippe name, logo, or model numbers. Patek Philippe did not make these watches. Under US law, selling a watch with a counterfeit trademark is a crime. Buying one for personal use carries less legal exposure than selling, but the watch can be seized at the border.
What the term covers
Patek Philippe is a Swiss watchmaker founded in Geneva in 1839. Its catalog includes the Calatrava, Nautilus, and Aquanaut lines. Replica sellers copy case shapes, dial layouts, and reference numbers. Some use the term "homage" for a watch that copies a design without the logo. A watch with the Patek Philippe logo is a counterfeit mark, not a homage.
Legal status in the US
15 U.S.C. § 1114 covers trademark infringement. 18 U.S.C. § 2320 covers trafficking in counterfeit goods. A first offense under § 2320 can bring up to 10 years in prison. US Customs and Border Protection can seize imports that bear a recorded trademark. Patek Philippe records its marks with CBP. A package with a replica watch can be detained, seized, and destroyed. The buyer loses the watch and the money.
How replicas differ from genuine watches
Genuine Patek Philippe watches use in-house mechanical movements. Most cases are 18k gold or platinum. The Nautilus uses steel. Replicas often use 316L steel with gold plating. Movements range from quartz to clone automatic calibers. Weight, finishing, and engraving differ. A genuine Nautilus 5711 has a precise case profile and a movement with specific finishing. Photos do not show these details. Serial numbers and papers are often forged. A serial number check with Patek Philippe is the only reliable test.
Price and quality tiers
Replica prices run from about $100 to $1,000. Lower tiers use quartz movements and plated cases. Higher tiers use automatic movements and sapphire glass. No tier matches the materials or tolerances of a genuine Patek Philippe. No replica carries a Patek Philippe warranty. Patek Philippe service centers do not service replica watches. Independent watchmakers may refuse to work on them because parts are not available.
Risks to the buyer
Customs seizure is the main risk. Resale is a second risk. A replica has no legal resale market in the US, and listing one for sale can trigger a trademark claim. Water resistance claims are often false. A watch rated "50 meters" may leak in a sink. Plated gold wears through at the lugs and caseback. Movement parts are hard to source. Repair costs can exceed the watch price.
Bottom line
"Replica patek philipppe" is a misspelling of Patek Philippe. A replica is a counterfeit trademark product. US law bans sale and import. The watch has no warranty, no service path, and no resale value. Check any watch against Patek Philippe records before you pay.