It seems that the nature of barcodes is a somewhat murkier and more confusing place than one would expect at first glance. As such this blog is going to attempt to offer greater depth and clarity on the issue and examine more specifically some areas of potential confusion.
So what is a barcode? It is an image which can be instantly read by a laser scanner to generate a sequence of numbers which a computer can connect information to. This number can vary from 8-14 digits long. That is literally all there is to it. However, since the purpose of the barcode is to differentiate each product from all other products just letting people pick their own codes clearly has flaws as a plan. Because the barcode is an international standard in order for it to be useful as a business tool any legislation would require international governmental business agreement which, without getting political, is unlikely to occur. As such the not for profit organisation GS1 has built up an international database of barcodes in various countries making it the industry standard such that even other companies buy GS1 codes to sell on and in the case of any dispute courts will err in the favour of GS1. The GS1 standard is that of 13 digits in Europe, the first 7-9 of which will form the Global Company Prefix and the last digit a random check number. The Company Prefix identifies your company and all barcodes with that Prefix belong to your company. This leaves between 5 and 3 digits and so 100,000 to 1000 barcodes registered to your company, hence a GS1 membership comes with a minimum 1000 barcodes.
Legality in barcoding is in most cases a matter of civil law. What this means is that while you could be taken to court for issues pertaining to a barcode you would be unlikely to find yourself under criminal charges. For example, if both your product and another had the same barcode one of you would need to withdraw your product and reprint at significant cost. Which product would need to be withdrawn would be decided by a civil court, when we talk of legality in barcoding we generally mean that which would lead the court to find in your favour.
Should such an instance arise it is then possible that the party found to be the legitimate owner of the barcode would feel the negative associations and problems with suppliers which have arisen deserve the redress of damages, which would again be sought in civil court. The only realistic situation in which an overlapped barcode would result in criminal charges would be as part of a fraud charge against a company consciously counterfeiting an existing game or if the damages mentioned above went unpaid.
Making It Up As You Go Along
Each shop will attach the details they wish to use to the code your product has printed on it, they won't necessarily refer back to the central GS1 database. Generating a barcode based on a number you made up is essentially free so why would you pay anyone anything for a registered barcode? In short, as suggested above, if there is an overlap in will be expensive and potentially destroy any fledgling relationship with distributors or retailers and registration with GS1 is how you defend yourself in such a case of overlap. Essentially registration with GS1 is the closest you can get to copyrighting or trademarking your barcode.
If this is only a significant concern when an overlap arises you might feel that if an overlap is unlikely its worth taking the risk of making up your barcode. After all since a barcode is 13 digits long the odds of meeting your barcode doppleganger are essentially 10,000,000,000,000 to 1 against. That is not however representative of the probability of your finding a problem because the barcode is split into sections, the first of which is registered to a company. As such there are between 10,000,000 and 1,000,000,000 significantly different barcode options because even if you pick a barcode unused on a product, if it overlaps a preexisting business registration you'll still hit issues. These still look like good odds until you consider that the primary purpose of barcoding is to enter distribution. Even for the relatively small scale distribution of a Kickstarter game its fair to assume you're hoping to be picked up by a company such as Esdevium and entered into a range of shops. If between the distributor's various boardgame companies and the shop's peripherals just 100 companies are involved your odds can drop as low as 10,000 to 1 against. Clearly these odds drop again if you distribute to a chain store and if you intend to distribute via Amazon or other on-line mass retail sellers you can assume the odds to be a practical certainty. Its worth mentioning that the algorithms on sites such as Amazon connect reviews to products using the company identifier section of the products barcode. What that means is that if you do sell with them and your product gets a poor review you will lower the rating of all products belonging to any company your code overlaps. Since your odds are higher of overlapping a company that chooses to buy barcodes 100,000 at a time this means you're likely to be lowering the ratings of products belonging to a large and probably aggressively defensive of their image company.
To use an analogy, using an unregistered barcode because it might not be noticed is rather like not getting car insurance because you might not get into an accident, reckless and ultimately anti-social.
Stack 'em High, Sell 'em Cheap
There are a range of companies selling barcodes whose status is unclear at best. The situation is that GS1 sells barcodes attached to a company prefix in a block, presumably to preserve the integrity of the system, meaning they can only be purchased from them in lumps of 1,000 - 100,000. The charge for doing so begins at a little over £100. As such there is a gap in the market for a company selling codes one at a time for £5 each, they make £4,900 for their 1,000 codes and a producer only wanting one code saves £95 so everyone should be happy. However, the GS1 website is quite clear that these companies are not approved by them and they give no guarantee that such barcodes are legitimate or unique. As such there is practically no way of telling if these companies have just made up a code for free and sold it on and as discussed above the odds of discovery are fairly low until you run quite a high number of checks. The selling on companies acknowledge GS1 as the industry standard and source of legitimate barcodes, which is a bit of a concern given that it doesn't recognise them in return. I've not personally heard of positive or negative stories relating to such companies but given the odds of discovery and ease of restarting an entirely digital company if negative stories should arise, not to mention the necessity to restart such companies with every 100,000 units sold, a lack of negative stories is probably not significant.
The selling on companies openly acknowledge that codes purchased from them will share a company identification not your own, something that GS1 state as making proper protection and identification of codes as impossible. There is a slightly odd statement on most of these sites relating to a class action against GS1 won by them in 2002. The basis of this statement seems to be that prior to 2002 GS1 sold barcodes in perpetuity but realised this would inevitably lead to a point where the system would need to be completely remodeled and so barcode life spans should be limited to the shelf life of the attached product. As such the membership process was instituted by GS1 and they attempted to recall any previously sold unused barcodes for reuse. The selling on companies, among others, fought and won a class action to stop this recall. I'm not entirely clear what relevance this class action has to the acceptability of selling on barcodes, since the only benefit to paying for any barcode comes from GS1 supporting your claim of singular ownership in any possible civil or related case and since they refuse to support any codes not used by their registered companies the failure to recall these codes seems entirely irrelevant. It should mean that a sold on barcode should at least have no chance of over lapping a legitimate GS1 barcode but in the event of over lapping a non-legitimate barcode you would have no specific support. In short you should be fine so long as everyone else is following the rules. Of course any advantage gained by paying for a sold on barcode is entirely dependent on their having been purchased from GS1 which, since GS1 do not support the practice, is impossible to check. This therefore relies entirely on the honesty of these companies who claim to have been selling the same block of barcodes since 2002. If they've been selling on average 100 a week then they're on about 83,000 sold at this point, when they couldn't have had more than 100,000 to sell in the first place. So one answer is to wait another 4 years and assume that any of them still selling are liars.
I always advocate caution in these issues, primarily because cutting corners without risk requires a significantly greater understanding of the issue than I possess. For barcodes the cost of a mistake can be significant and proper registration is both simple and reasonably priced. As such I suggest registration with GS1.