information you've seen but never thought about before. Some of the label is just marketing hype, but if you are looking at a bottle of American wine, the words "Estate Wine" or "Estate Bottled" do have an important meaning controlled by law.
While terms like "Reserve" or "Old Vines" have no rules behind them, the use of "Estate" on wine is regulated by the Bureau of Alcohol, Tobacco, Firearms and Explosives.
There are three requirements to fit the definition of an estate wine.
1. Wines with an "estate bottled" designation must also designate an appellation of origin or an AVA (American Viticultural Area) and both the winery and vineyards must be located there. Appellation and AVA are terms for an established wine growing region. You can't be a Napa winery and source grapes from Lodi and call it an estate wine.
2. The grapes must come from vineyards owned or controlled by the winery. If you own a winery and purchase fruit from another vineyard owner, you must have control over the vineyard. This would include decisions on what grapes to plant, irrigation, cultivation and other important decisions. If you don't control the vineyard, you can't put "estate" on the bottle.
3. The wine must have been produced, from the initial crush to bottling, in a continuous process without leaving the winery's premises.
Usually estate wines cost more because of the extra care and effort that goes into production of the wine. This doesn't mean that non-estate wines are bad. Some wines are labelled "California" for example, with grapes from several different wine growing areas -- but they can still produce exceptional wines.
By the way, although the term "Reserve" isn't regulated if you are buying from a respected winery, you should feel pretty confident that there is something special about the wine. "Reserve wines" are typically considered the winery's best or upper echelon wines and good wineries try to live up to that standard. With struggling or unknown wine producers: buyer beware.