Patent proceedings before the patent and market court: what to do in the first days after being served is to secure the evidence, confirm the response deadline, and decide whether to seek a stay, an invalidity counterclaim, or an interim injunction before the pleadings the court will use to frame the case are finalised. Everything that follows in the litigation builds on choices made in that opening window.
Who this concerns
This concerns two groups of companies, and the first steps look different depending on which side of the writ a company sits on.
The first group has just been served: a competitor, a former licensee, or a patent holder outside Sweden has filed a claim before the Patent and Market Court alleging infringement, and a formal response is now due. The second group is on the other side, weighing whether to file, and needs to understand what happens once the claim reaches the court rather than staying a commercial disagreement.
Both groups share the same exposure if nothing happens in the first days. A missed deadline can produce a judgment on the terms the other side proposed, without the company's own arguments ever being tested. Evidence that would have supported non-infringement or invalidity, internal correspondence, prototypes, prior product versions, tends to be discarded, overwritten, or forgotten within weeks of a dispute becoming live, long before the case reaches a hearing. The company that acts in the first days keeps the option to shape the dispute; the company that waits inherits whatever the other side has already built into its filing.
Companies with an active patent portfolio, whether as licensor, licensee, or manufacturer working close to a competitor's claims, are the most frequent audience for this situation, because the risk of an infringement claim tracks commercial success rather than legal exposure in the abstract.
What the law says
The framework governing patent litigation in Sweden channels these disputes through a single specialised forum, the Patent and Market Court, rather than through the general courts. That concentration exists because patent disputes combine legal argument with technical fact-finding that ordinary civil courts are not set up to handle at scale.
Under Swedish law as it currently stands, a defendant served with a patent infringement claim has a formal opportunity to respond before the court moves the case forward, and a failure to respond within the time set by the court carries the risk of a judgment being entered on an uncontested basis. The exact number of days allowed is set by the court on the facts of each case rather than fixed in advance, which is precisely why confirming the deadline in writing, rather than assuming it, is the first practical task.
Under Swedish law as it currently stands, a defendant is also entitled to raise the invalidity of the asserted patent as a defence within the same proceedings, rather than needing to bring a separate action. That right changes the shape of the whole case: a dispute that starts as "did we infringe" can become "is there anything left to infringe," and the earlier that possibility is assessed, the more it can influence strategy rather than simply react to the other side's filing.
Appeals from the Patent and Market Court proceed to the Patent and Market Court of Appeal, and under Swedish law as it currently stands that appellate route is the only avenue available; there is no separate route through the general courts of appeal for the same dispute.
How it works in practice
Reading the writ for what it actually claims
The writ names specific patent claims and specific acts of alleged infringement, and the response has to engage with exactly those claims and acts, not with the dispute as it has been discussed commercially. A response drafted from memory of the underlying disagreement, rather than from the text of the writ, tends to leave gaps the other side can exploit later in the proceedings.
Confirming and calendaring the response deadline
The deadline set by the court is the single fact that determines everything else about the first days. It should be confirmed in writing with the court registry rather than assumed from the date on the writ, and calendared with enough margin to allow for internal sign-off, translation of technical material where needed, and instruction of a patent attorney or technical expert.
Securing evidence before it moves
Prior art documents, product development records, and internal communications about the disputed technology should be preserved as soon as a dispute becomes foreseeable, not once the writ arrives. Version control systems get overwritten, engineers change employer, and prototypes get scrapped in the ordinary course of business; none of that waits for litigation timetables.
Deciding on an invalidity counterclaim
Whether to challenge the patent's validity, rather than only argue non-infringement, is a strategic decision that has to be made early because it changes what evidence matters and what expert input is needed. A counterclaim raised late in the proceedings is treated with more scepticism by the court than one raised at the outset.
Interim injunctions and how they change the timetable
Either side can seek an interim injunction, and a request for one compresses the whole timetable because the court has to decide it quickly, often before the substantive case has been fully argued. A company facing an injunction application needs to respond within days, not weeks, which is one reason the first days after being served matter disproportionately.
Technical evidence and expert opinions
Patent disputes turn on how a skilled person in the relevant field would read the claims, and that reading is established through expert evidence rather than argument alone. Instructing a technical expert early, before positions have hardened in correspondence, produces opinions that are more useful to the case than ones drafted to defend a position already taken publicly.
Settlement discussions running alongside the case
Filing a formal response does not close the door to settlement, and in practice many patent disputes before the Patent and Market Court are resolved by agreement before judgment. Keeping a parallel settlement track open, without letting it delay the procedural deadlines, tends to produce better outcomes than treating litigation and negotiation as sequential rather than simultaneous.
Cross-border patents and foreign parent companies
Where the patent holder, the licensee, or the group's parent company sits outside Sweden, the first days involve additional questions that a purely domestic dispute would not raise: which entity in the group actually holds standing to sue or be sued, how instructions and evidence move across the border without delay, and whether a foreign parent's involvement in product development creates exposure separate from the Swedish subsidiary's. These questions should be answered before the response is drafted, not discovered afterwards.
What to check before responding
- Which specific patent claims and acts of alleged infringement the writ actually identifies
- The exact deadline set by the court, confirmed in writing rather than assumed
- Whether an interim injunction has been requested alongside the main claim
- Which group entity holds the contracts, product rights, and communications relevant to the dispute
- Whether prior art exists that could support an invalidity defence
- Whether internal records and prototypes relevant to the dispute are being preserved
Frequently asked questions
What happens if the response deadline to a patent claim before the Patent and Market Court is missed?
A missed deadline exposes the defendant to a judgment entered on the claimant's version of events, without the court considering arguments that were never filed. Courts retain some discretion to admit a late response in limited circumstances, but that discretion is not something a defendant should plan around; treating the deadline as fixed protects the position far more reliably.
Can a defendant challenge the validity of the patent within the same proceedings?
Yes. Under Swedish law as it currently stands, invalidity can be raised as a defence within the infringement proceedings themselves, rather than requiring a separate action. This turns the case into two questions, infringement and validity, and the earlier both are assessed together, the more coherent the overall strategy can be.
How does a request for an interim injunction affect the timeline of patent proceedings?
An injunction request forces the court to decide quickly, often on a compressed record, before the substantive dispute has been fully argued. For the party facing the request, that compression means the ordinary window to prepare a considered response effectively disappears, and evidence or expert input needs to be ready far earlier than it would for the main proceedings.
The numbers
Cost in patent proceedings before the Patent and Market Court is driven by the complexity of the underlying technology, the number of claims in dispute, and how much technical expert evidence each side needs to commission, rather than by the size of the claim on its face. A dispute involving a single mechanical feature costs materially less to run than one involving software implementation or biotechnology, where expert reports and cross-examination on technical points take up most of the court's and the parties' time.
An invalidity counterclaim increases cost because it doubles the technical questions the court has to resolve, but it can also shorten the overall dispute if it succeeds, since a finding of invalidity ends the infringement claim regardless of the facts on infringement itself. An interim injunction request increases cost in the short term because it forces rapid preparation, but it can reduce total cost if it either resolves the dispute early through settlement pressure or is refused in a way that clarifies the merits for both sides.
The timeline is set by the court's own calendar and by how complete the parties' submissions are at each stage, rather than by a fixed statutory period; a case with well-prepared evidence from the outset moves through the court's process more predictably than one where gaps in the record have to be filled as the case proceeds. Losing party costs rules mean that the unsuccessful side typically bears a share of the other side's litigation costs, which raises the stakes of an early assessment of the merits before costs accumulate on either side.
Where it usually goes wrong
Companies most often lose ground in the first days, not at trial. The following patterns recur often enough to be worth naming directly.
Treating the deadline as approximate rather than fixed is the single most common failure, usually because the writ is read as a starting point for negotiation rather than as the beginning of a formal timetable the court controls.
Assuming that non-infringement is the only available defence, without assessing invalidity early, leaves a strong argument unused until it is too late to develop the supporting evidence properly.
Instructing a technical expert late, after correspondence has already committed the company to a factual position, produces expert opinions that defend that position rather than test it, which weakens the case rather than strengthening it.
Where the patent holder or a key witness sits outside Sweden, delays in getting instructions and documents across the border in time for the deadline are common and largely avoidable if identified in the first days rather than discovered close to the deadline.
Assuming settlement discussions pause the clock. They do not, and a company that stops preparing its formal response because talks are ongoing can find itself out of time if the talks fail.
This is also where the analysis stops being something a company can safely finish alone. Assessing whether an invalidity defence is realistic, whether an interim injunction is likely to succeed, and how the group's cross-border structure affects who should be named in the response requires reviewing the specific patent, the specific writ, and the specific product against each other; general principles do not settle those questions.
What to do next
The work described above, confirming the deadline, mapping the claims against the product, deciding on an invalidity defence, sits within a company's own control in the first days after being served. What sits outside that control is an assessment of how strong each option actually is on the facts of this dispute, which needs the writ, the patent, and the product reviewed together rather than in the abstract.
The intellectual property and UPC practice at Lodline works from exactly that starting point: the writ and the patent in hand, not a general description of patent litigation. Where a company is inside the first days of a Patent and Market Court dispute and needs that review done before the deadline runs out, book an assessment rather than treat the deadline as something to manage informally.