US 4373133

I'll verify the patent details and check for any CAFC/litigation activity involving this specific number.

Bottom line first

Important caveat on the litigation/docket check: I searched for Federal Circuit 2026 docket activity tied to this specific number and found none. The searches did not surface any CAFC appeal, district court action, or PTAB proceeding involving U.S. Pat. No. 4,373,133. I could not query the CAFC docket or USPTO PatentCenter directly in this session, so this is a negative search result, not a certification. It is also consistent with the record: the patent shows "Expired – Fee Related," with maintenance fees lapsing and an entry for "PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362" (recorded 2018‑01‑22, effective lapse 1995‑02‑08) and an anticipated expiration of 2000‑12‑30. An expired, unenforceable patent is unlikely to generate live 2026 appellate activity.

Bibliographic summary — US 4,373,133 A

Corroboration from the searches (independent of the provided text): an EPO search report cites "US 4 373 133 A (STURGEON PHILIP L ET AL) 8 February 1983," and a PCT search annex lists the family pairing GB‑A‑2068132 (05/08/81) → US‑A‑4373133 (08/02/83). Later documents (EP 1 039 275 A1; EP 3 147 850 A1; WO 86/05270) cite it as background art in the self-checkout/weight-verification field. These all confirm the bibliographic data rather than contradict it.

Abstract (as published)

To reduce time spent at the check-out of a self-service shop, each customer is provided with an electronic recording unit mounted on the receptacle used to collect items for purchase. The unit has a memory store for data identifying the items collected. The prices and gross weights of the items are summed, e.g. by extraction of data from a data store in the unit or from data input from a bar code on the items themselves. The collection of items is weighed as a whole at the checkout for comparison of the measured weight with the computed sum of the gross weight of the individual items.

The inventive concept in one paragraph

This is an early self-scanning / mobile-scan checkout patent. The shopper scans items with a light pen into a unit clipped to the trolley or basket; the unit records item identities, sums prices, and sums gross weights (including each item's allowed weight tolerance). At the checkout the whole collection is weighed once and the measured weight is compared against the computed aggregate weight within the accumulated tolerance band. If the two agree, the shopper pays the aggregate price without item-by-item handling; if not, the collection is repriced conventionally. The weight-tolerance verification is the anti-fraud backbone of the concept.

Independent claims — plain language

Claim 1 — "A self-service shop" (system claim). A shop having four cooperating parts:

1. (a) storage locations (shelves) for items;
2. (b) multiple movable receptacles (trolleys/baskets) customers use to assemble a collection;
3. (c) multiple movable electronic recording units tied to those receptacles, each containing:
   • (i) a memory store that records at least the identity data of selected items;
   • (ii) input means to enter the identifying information;
   • (iii) price summing means producing an aggregate price for the collection; and
   • (iv) a visual display of that aggregate price while the collection is being formed (i.e., in-aisle running total, not just at checkout);
4. (d) weight summing means producing an aggregate gross weight from the items recorded in the memory store; and
5. (e) at least one check-out station with a scale to weigh the assembled collection and produce a measured gross weight, which can then be compared to the summed aggregate gross weight.

Note the claim language deliberately says "at least data identifying the items" and does not itself require tolerance/standard-deviation data — that tolerance teaching lives in the specification (and would be relied on for claim construction).

Claim 2 — "Container apparatus for use by a customer in a self-service shop" (apparatus claim). A trolley/basket unit comprising:

1. (a) a container to receive the collection;
2. (b) an electronic recording unit mounted on the container whose memory store records both (i) identifying data per item and (ii) data relating to aggregate weight and price; and
3. (c) input means for entering the identity data at the time each item is added.

The unit must further include:

1. (i) programmed data storage means holding weight and price data for the store's items;
2. (ii) programmed calculation means that takes the scanned identity data, looks up the corresponding weight/price from the data storage, computes aggregate weight and price, and writes them to the memory store; and
3. (iii) display means showing the aggregate price during formation of the collection.

Claim 2 is the "look-up table on the cart" claim — the unit carries its own price/weight database (the specification's preferred form uses a magnetic bubble memory, ~128 KB), so only item identity need be encoded on the goods.

Dependent claims

• Claim 3 (dep. 1): each movable receptacle has one of the movable recording units mounted on it.
• Claim 4 (dep. 1): the unit contains its own data store of price and gross weight for stocked items, and the price/weight summing means compute the aggregates from the scanned identity data plus that data store (i.e., the on‑board‑database configuration imported into the shop claim).
• Claim 5 (dep. 1): the unit displays the price of the last item entered, in addition to the aggregate.

Observations worth flagging

• No method claim issued in the US. Despite the title beginning "Method for producing a bill…" and the specification setting out a "first aspect" as a four-step method (record identity → sum price → sum gross weight → weigh collection and compare), the granted claim set (5 claims) contains only a system claim (1) and an apparatus claim (2), with 3–5 dependent. The method is described but not claimed here — a common outcome where method claims were withdrawn or not pursued during prosecution.
• The weight-tolerance feature is specification-supported but not on the face of the claims. The specification states the per-item gross weight indication includes the allowable deviation from the mean (standard variation), and that the aggregate gross weight indication includes a summation of those variations to define "an aggregate predetermined limit." That tolerance-summation idea is what later self-checkout art (e.g., the EP 3 147 850 family cited above) built upon.
• Two commercial architectures are taught: (1) full data (identity + price + gross weight + tolerance) encoded in an EAN/UPC bar code on the item or shelf, with the unit summing totals itself; or (2) identity-only bar codes plus an on‑board data store (bubble memory) in the unit, or a central store database consulted at the checkout — the latter eliminating per-item price marking entirely.
• Secondary features not claimed: item counting for stock‑taking/fraud detection, printing an itemized receipt from a register reading the unit's memory, electronic interface between the unit and the scale/register with red‑green accept/reject signalling, reset-on-disengagement, and shopper aids (aisle-locator, timer/alarm, promotional loudspeaker).
• Uncertainty: I have not independently verified the inventors' names, assignment chain, or legal status against USPTO PatentCenter/Assignment records in this session; the values above come from the authoritative Google Patents full text you supplied, and the parts I could cross-check (patent number, title, inventor surname, issue date, GB family member) were confirmed by third‑party citations. No assertion here should be taken as a legal conclusion about validity, enforceability, or ownership.