The ownership of grapes on their way from the vineyard to the winery comes down to the details of the contract between the parties, insurance brokers warn.
As Marlborough gears up for the busy part of harvest, the insurance firms are warning that experience shows many things can go wrong before the grapes get to the winery, such as contamination during harvest or a truck spill on the road.
Hutchison Rodway Marlborough director Chris Lane said if a spill or contamination of the grapes occurred it could be hard to determine who was responsible.
"Often there's a no-man's land between the vineyard and the winery.
"It all depends on the agreement between the growers and the winery."
Many contract growers have a supply contract where the winery organises harvest and transport, he said.
"[But] wineries often only take responsibility once it's in the building."
This is where the confusion often lies, he said.
"It's probably just not something that people have thought of a great deal."
Growers think that once their crop is off [their premises] it is not their responsibility, he said. He has had several cases in past years where growers have lost their harvest through mishaps on the way to winery, Mr Lane said.
A few years ago, he dealt with a big claim involving grapes being contaminated by hydraulic fluid on the harvester. The winery and harvesting company battled it out in court for about $250,000, Mr Lane said.
"The winery had to wear the cost," he said.
Other regular accidents were spillages out of a harvester or the gondola, which could be worth up to $5000.
Crombie Lockwood Blenheim branch director Wayne Wiffen has also dealt with cases involving grape spillages and contaminations.
There are normally always four parties involved - growers, harvesters, truck companies and wineries, he said.
"It is often misunderstood who carries the the risk between the vineyard and the winery."
"It is a grey area," Mr Wiffen said.
The estates potentially have the most responsibility, as it is their property - they own the fruit, he said.
"The important thing is, if they [wineries] understand where the risk is they should be insuring themselves.
"Everyone is flat out. It's a busy time for this industry - that's when accidents occur."
- The Marlborough Express