Learn Hardcore Croatian: U našem ugovoru piše da su pravila napisana od vlasnika. - In our contract it says that the rules were written by the owner.

The literal meaning seems to be “In our contract writes that the rules are written by the owner.” How should I really understand the structure of this sentence?

Literally, word by word, it is something like:

U našem ugovoru – In our contract
piše – writes / it writes → really means “it says” / “it is written” here
da – that
su pravila napisana – the rules are written / have been written
od vlasnika – by the owner

A good natural English translation of the whole sentence would be:

“Our contract says that the rules were written by the owner.”
or
“In our contract it says that the rules were written by the owner.”

Key points:

Croatian uses piše impersonally here, so there is no explicit subject (it is implied).
da su pravila napisana od vlasnika is a that-clause giving the content of what the contract “says”.

What exactly does piše mean here? Is the contract “writing” something?

Piše is the 3rd person singular present of pisati (to write), but in this kind of sentence it’s used impersonally and idiomatically.

Pisati (present): pišem, pišeš, piše…
U našem ugovoru piše… – literally “In our contract it writes…”, but idiomatically:
- “In our contract it says…”
- “It is written in our contract…”

So:

There is no real subject like he/she/it doing the writing at this moment.
It’s a fixed way to say what is written somewhere (in a contract, book, article, etc.):

Examples:

U ugovoru piše da… – The contract says that…
Na računu piše datum. – The date is written on the bill. / The bill shows the date.

Why is it u našem ugovoru and not u naš ugovor? What case is that?

U našem ugovoru is in the locative case, because the preposition u here expresses a static location (in, inside).

Nominative (dictionary form): ugovor – contract
Locative singular (masculine): (u) ugovoru – in the contract

The possessive pronoun naš must agree with ugovor in gender, number, and case:

Nominative: naš ugovor – our contract
Locative: u našem ugovoru – in our contract

So:

u + locative for being in something:
- u gradu – in the city
- u ugovoru – in the contract
- u našem ugovoru – in our contract

What is the role of da in piše da su pravila napisana…? Could I leave da out?

Da is a subordinating conjunction meaning “that”, introducing a content clause (reported/indirect statement).

U našem ugovoru piše da…
→ Our contract says that…

The part after da is a full clause:

da su pravila napisana od vlasnika
→ that the rules were written by the owner

You cannot normally drop da here. Saying:

✗ U našem ugovoru piše su pravila napisana…

would be wrong. You really need:

U našem ugovoru piše da su pravila napisana…
In our contract it says that the rules were written…

Why is it da su pravila napisana, with su before pravila? Could I say da pravila su napisana?

This has to do with clitic placement. The word su (a form of biti, to be) is a clitic and in Croatian clitics tend to appear in second position within a clause.

In the clause:

da su pravila napisana

the first word is da, so the clitic su naturally comes next, in second position:

[da] [su] pravila napisana

This is the most natural order.

You could hear da pravila su napisana, but it sounds marked/emphatic or even awkward in many contexts. The neutral, standard form is:

da su pravila napisana

Compare:

Pravila su napisana. – The rules are written / have been written.
(here, pravila is first, so su comes second)

In short:

Use da su pravila napisana as your default pattern.

Is su pravila napisana a past tense like “were written” or a present state like “are written”?

The structure su + past passive participle (napisana) can express both:

A resulting state (present):
- Pravila su napisana.
  → The rules are written (they stand written; that is their current state).
A past passive event:
- Pravila su napisana (od vlasnika).
  → The rules were written / have been written (by the owner).

English forces you to choose between are written, were written, have been written, but Croatian “su napisana” can cover both, and the exact nuance depends on context.

Here, in “U našem ugovoru piše da su pravila napisana od vlasnika”, English speakers will usually understand and translate it as:

“…that the rules were written by the owner.”
or
“…that the rules have been written by the owner.”

Why is pravila (rules) plural neuter, and how does agreement work with su and napisana?

Pravila is the nominative plural neuter of pravilo (rule).

Singular: pravilo – a rule
Plural: pravila – rules

In pravila su napisana:

pravila – subject, neuter plural
su – 3rd person plural of biti (they are / they have been) → agrees in number
napisana – past passive participle of napisati, in neuter plural form

Important detail: the neuter plural participle form looks the same as the feminine singular:

Masculine sg: napisan
Feminine sg: napisana
Neuter sg: napisano
Masculine pl: napisani
Feminine pl: napisane
Neuter pl: napisana

So in our sentence, napisana is neuter plural, agreeing with pravila, not feminine singular.

Full agreement:

pravila (N pl n)
su (3rd pl)
napisana (N pl n participle)

What’s the difference between napisana and something like pisana? Why use napisana od vlasnika?

Both come from verbs related to pisati (to write), but they differ in aspect and meaning:

pisati – imperfective (to write, ongoing, habitual, process)
- past passive participle: *pisan, pisana, pisano, pisani, pisane, pisana
- pisana pravila – rules that are/were being written, or in some contexts written rules (more neutral/less focused on completion)
napisati – perfective (to write with a sense of completion: “to finish writing”)
- past passive participle: *napisan, napisana, napisano, napisani, napisane, napisana
- napisana pravila – rules that have been written and completed

In a legal context (a contract), we usually care that the rules have been fully written down / completed, so napisana (from napisati) is more appropriate.

Napisan(a) often suggests:

The action of writing has been carried out and finished.

Why is it od vlasnika to mean “by the owner”? Could I say po vlasniku or something else?

In Croatian, the agent in a passive is usually expressed with od + genitive or od strane + genitive:

od vlasnika – by the owner
od strane vlasnika – by the owner (more formal)

Here:

vlasnik – owner (nominative)
vlasnika – genitive singular (after od)

So:

napisana od vlasnika – written by the owner

Using po is not the standard way to express the agent in a passive in Croatian. You might see po in some fixed expressions, but for a normal “by X” in a passive sentence, use:

od + genitive
or od strane + genitive (very common in legal/official language):

Examples:

Knjiga je napisana od poznatog autora.
Knjiga je napisana od strane poznatog autora.
→ The book was written by a famous author.

Are there more natural or alternative ways to say the same thing in Croatian?

Yes, there are a few very natural variants with slightly different style:

Keep the same structure, maybe more formal:
- U našem ugovoru piše da su pravila napisana od strane vlasnika.
  (by the owner → od strane vlasnika is typical legal style.)
Use another common verb for “it says / it states”:
- U našem ugovoru stoji da su pravila napisana od vlasnika.
  (stajati = to stand, but in this context to state.)
Use an active sentence instead of passive:
- U našem ugovoru piše da je vlasnik napisao pravila.
  → Our contract says that the owner wrote the rules.

All are correct; the original sentence is understandable and fine, though many speakers (especially in formal writing) might favor “od strane vlasnika” or rewrite passives into actives.